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THE 



PALiEONTOGRAPHICAL SOCIETY. 



INSTITUTED MDCCCXLVII. 



LONDON 



MDCCCCIV — MDOCCCXIII. 



MONOGRAPH OF THE CRETACEOUS LA:\IELLIBRANCHIA 

OF ENGLAND. 

VOL. ii. 



ORDER OF BINDING AND DATES OF PUBLICATION 



PAGES 


PLATES 


ISSUEU IN VOL. 
FOB YEAB 


PUBLISHED 


General Title-page and Contents 





1912 


February, 1913 


1—56 


I— VII 


1904 


December, 1904 


57—96 


VIII— XI 


1905 


November, 1905 


97—132 


XII— XIX 


1906 


December, 1906 


133—180 


XX— XXVII 


1907 


December, 1907 


181—216 


XXVIII— XXXIV 


1908 


December, 1908 


217—260 


XXXV— XLIV 


1909 


December, 1909 


261—284 


XLV— L 


1910 


January, 1911 


285—340 


LI— LIV 


1911 


February, 1912 


341—473 


LV— LXII 


1912 


February, 1913 



1"'^/ A MONOGRAPH 



CRETACEOUS LAMELIiBRANCHIA 



ENGLAND. 



BY 

he:^ry woods, m.a., 

UNIVERSITY LECTURER IN PAL^OZOOLOOT, CAMBRIDGE. 



VOL. II. 




LONDON: 
PRINTED FOR THE PAL^ONTOGRAPHICAL SOCIETY. 

1904—1913. 



PUINTEI) IIV AULAKI) \SI> SON. LONDON AND DOUKINQ. 



CONTENTS OF YOL. TI. 





PAQB 


Ostrea ... 


342 


Exogyra 


395 


Lima ... 


1 


(Plagiostoma) 


10 


(Acesta) 


25 


(Mantellum) 


28 


(Ctenoides) . . . 


40 


„ (Limatula) ... 


45 


(Limea) 


53,425 


Pteria (Oxytoma) 


57 


„ (Pseudoptera) 


63.425 


Aucella ... 


69 


Aucellina 


72 


Gervillia 


74,425 


Perna ... 


87 


luoceramus 


262,433 


Piuna ... 


96 


Astarte... 


102 


„ (Eriphyla) 


113,426 


Opis 


118 


Cardita ... 


121 


Cvassatellites 


128,426 


Anthouya 


130.426 


Cyprina... 


131.427 


Trapezium 


148 


Isocardia 


151 


Lucina .. 


152 


Corbicella 


157 


Spbsera... 


157 


Mutiella 


160 


Unicardium 


162,428 


Thetironia 


165 


Tellina ... 


171.429 


,, (Palseomoera) 


173 


(Linearia) 


175 


Mactra ... 


177 


Ptychomya 


179 



VI 



f 'R KTAf'EOUS LAMETJ.IBRANCHTA. 











PAQE 


Dosiniopsis ... ••• ••• •• 1°^ 


Cypriinoria (Cvtlorisma) 




183,431 


Clomentia (Flavoutia) 




189 


Callista... 




.. 


192 


Tajies (Icauotia) ... 




.. 


431 


Protocanlia 






194 


Cardium 






201 


(Grauocariliiiin) 






205 


Toucasia 






207 


Gyropleura 




208 


Diirauia... 




420 


Corbula 






210 


Pharus... 






217 


Solecurtus (Azor ?) 






218 


Leptosoleu 






219, 432 


Pauopea 


■ . 




221 


Martesia 


.. 




231 


Turnus ... 






233 


Teredo... 






237 


Plectomya 






238 


Anatiua (Cercomya) 








238 


Thrac-ia... 








240.432 


Pholadoniya 








245 


Myopholas 








253 


GouioHiya 








254 


Pk'iiroinva 








256 


Liopistha (Psilomvaj 




.. 




257 


Cuspidaria 




.. 




259 


Additions and Corrections 








423 


Tables of Distribution 








434 


Bibliography 




., 




.449 


Index 








462 



THE 



PAL.EONTOGRAPHICAL SOCIETY. 



INSTITUTE I) :\II»('CCXLVir. 



VOLUME FOR 1904. 



LONDON 



MDCCCCIV. 



A MONOGRAPH 



CRETACEOUS LAMELLIBRANCHIA 



OF 



ENGLAND. 



BY 



HENRY WOODS, M.A. 

UNIVERSITY LECTUREK IN rALiOZOOLOGT, CAMBRIDGE. 



VOL. IL PART I. 
LIMID^. 

Pages 1— 5tj: Plates I— A'll. 



LONDON : 
PRINTED FOli THE PAL.EONTOGKAPHICAL SOCIETY. 

11)04. 



PRINTED BY ADLARD AND SON, LONDON AND DOKKINO. 



DESCRIPTION OF SPF.CIES. 



Familij—LmmjE, d'Orbignij. 

Genus — Lima, /. G. llruguierc, 1797. 

(' Eucyc. method.,' Tabl. Vers., pi. ccvi.) 

Lima canalifeka, Gold/ass, 1836. Plate L 

1836. Lima canalifeea, A. Gohlf'uss. Petref. Germ., vol. ii, p. 89, pi. civ, fig. 1. 
1839. — — H. B. Geinitz. Cliar. d. Schicht. u. Petref. des siiclis. 

Kreidegeb., pt. i, p. 24. 

— — MULTicosTATA, Geinitz. Ibid., p. 24, pi. viii, fig. 3. 

1841. — CANALIFEEA, F. A. Boiner. Die Versteiu. d. uord-deutscli. Kreidegeb., 

p. 56. 

— — LATicosTA, Romer. Ibid., p. 57, pi. viii, fig. 9. 

1843. — MVh-ncosTATA, H. B. Geinitz. Die Versteiu. von Kiesliugswalda, p. 23, 

pi. vi, fig. 10. 
1846. — LATICOSTA, A. E. Beuss. Die Verstein. der bohm. Kreideformat., 

pt. 2, p. 34. 

— — MtTLTicosTATA, Beuss. Ibid., p. 34, pi. xxxviii, figs. 7, 8, 18. 

— — — H. B. Geinitz. Grimdr. d. Versteiu., p. 472. 

1850. — CANALIFEEA, Geinitz. Das Quadersaudst. oder Kreidegeb. in Deutsch- 

laud, p. 190. 

— — MULTICOSTATA, Geiuitz. Ibid., p. 192. 

— — CANALIFEEA, A. (VOrhi<jHij. Prodr. de Pal., vol. ii. p. 167. 
? — — MULTICOSTATA, d'Orhiijmj. Ibid., p. 248. 

— — LATICOSTA, d'Orltigny. Ibid., p. 249. 

1863. — CANALIFEEA, A. Kiinth. ZeitscliT. d. deutsch. geol. Gesellsch., vol. xv, 

p. 726. 

— — — B. Drescher. Ibid., vol. xv, p. 356. 

? 1868. — MULTICOSTATA, E. Eichwakl. LetLsea Kossica, vol. ii, p. 459. 

1870. — MULTicosTA, F. J. Piclet and G. Campiche. Foss. Terr. Crct. St«?. 

Croix (Mater. Pal. Suisse, ser. 5), p. 174. 

— — CANALIFEEA, Pictet and Campiche. Ibid., p. 175. 

1872. — — H. B. Geinitz. Das Elbthalgeb. iu Sachsen (Palroon- 

tographica, vol. x.\, j)!. 2). p. 38, 
pi. ix, tigs. 6 — 8. 

1 



2 CRETACEOUS LAMELLIBRAXCHIA. 

1876. Lima canalifera, D. Brauns. Zeitschr. f . d. gesammt. Natui-wiss., vol. xlvi, 

p. 386. 

1877. — — A. Fritsch. Stud, im Gebiete der bohin. Kreidofuruiat. : 

II, Weissenberg. u. Mabiitz. Scliiclit., 
p. 132, fig. 117. 
1893. — cf. CANALIFEEA, B. Miclutd. Zeitschr. der deutscli. geol. Gesellsch., 

vol. xlv, p. 242. 
189g. — CANALIFEEA, G. Midler. Mollusk. Uuterseuou. v. Braimscliweig u. 

Ilsede (Abhaudl. d. k. preussiscli. geol. 
Landesaust. N.F., Heft 25), p. 28. 
lyOl. — — if. Imheller. Kreidebild. am Stallauer Eck (Palaeou- 

tograpliica, vol. xlviii), p. 32, pi. iii, fig. 10. 
— — — F. Sturm. Jabrb. d. k. preussisch. geol. Landesaust. 

fiir 1900, vol. xxi, p. 90. 

Description. — Sliell moderately convex, oval or subtriangular ; height a little 
greater than length ; outline rounded, except the antero-dorsal margin, which is 
nearly straight and rather long. Apical angle from 105° to 110°. Umbones 
rather small, close together. Anterior area slightly depressed, with small radial 
ribs. Anterior ears small ; posterior larger, with growth-lines and faint radial 
ribs. 

Ornamentation consists usually of 18, but sometimes of as few as 14 or as many 
as 21 very strong, rounded, straight ribs, which are separated by broader furrows. 
In well-preserved specimens numerous concentric linear ridges occur on both rijjs 
and furrows, and projecting growth-ridges are seen at regular intervals on the 
ribs. 

teasurements : 

(3) (1) (5) 

. 52 . 43 . 32 mm. 
. 54 . 44 . 35 „ 

(1 — 6) Uj^per Grreensaud, Ventnor. 

Ajjlnities. — An exact comparison of the English specimens with the foreign 
examples of Limn canalifera is rendered difficult owing to the fact that the former 
have the shell well preserved Avhilst the latter occur chiefly as casts. In both 
cases the number and breadth of the ribs show considerable variation. The fine 
concentric ornamentation is the same in both, as is shown by Goldfuss' figure, but 
in some of the best preserved English specimens there occur also transverse 
ridges on the ribs at regular intervals. Somewhat similar ridges are shown in 
Goldfuss' figure, but they seem to be present chiefly on the sides of the riljs and 

' In all species of Lima (unless otherwise stated) this is moasured obbquelv to the hiui;e-Uue so 
as to give the greatest height . 



Measurements : 








(1) 


(2) 


Length 


7(» 


. 56 


Height' 


70 


58 



LIMA. 3 

in the neighbourhood of the umbo only. With the exception of tliis cliaracter the 
Eng-b'sh specimens agree closely with the foreign examples, and this difference 
may very well lie due to the latter being much less perfectly preserved than the 
former. Moreover, in some English specimens the ridges mentioned are partly or 
entirely wanting. 

The English examples occur at a lower horizon than those found abroad, 
namely, in the zone of Feden oftj^er. The foreign specimens are found in the 
Turonian and Senonian, and possibly also in the Cenomanian, and, like the English 
examples, they occur chiefly in beds of a sandy nature. This last fact may account 
for the absence of the species in the English Chalk, during the deposition of which 
the sea-iloor was formed of ooze and was at a greater depth. 

Lima Etalknii, Pictet and Campicho,' from the Yalauginian, presents some 
resemblance to L. canalifera, but has a smaller apical angle ; the character of its 
fine ornamentation is unknown. 

Type. — Goldfuss' specimens came from the Senonian of Quedlinl)urg, Haltern 
and Regensburg. 

fi/.'^friliiifiov. — Upper Greensand (zone of Frrirn a><]irr) of Vontnor. 



Ltma GAT.T.TENNKr, iVOrhi(jmi, 1847. Plate II, figs. 1'/ — c. 

1847. Lima Gallienniana, A. d'Orbigny. Pal. Franc. Terr. Crrt., vol. iii, p. 548, 

pi. ccccxx, figs. 1 — 3 {GalUennei on 
plate) . 
1850. — — — Proclr. de Pal., vol. ii, p. 166. 

1854. — Galliennei, /. Morris. Cat. Brit. Foss., ed. 2, p. 171. 
1867. — — E. Gve'ranger. Allium Pak'ont. de la Sarthe, p. 18, 

pi. xxiii, figs. 23, 24. 
1869. — — F.J. Fictci and G. Camjnche. Foss. Terr. Cri't. Sto. 

Croix (Mater. Pal. Suisse, ser. 5). 
p. 168. 
1871. Eadula Galliennei, F. Sloljczka. PaloDont. Iiidica, Cret. Fauna S. India, 

vol. iii, p. 414. 

J)r.<!rnpfi(iv. — Shell compressed, more or less oblong with rounded margin ; 
height greater than length. Antero-dorsal margin straight or slightly coTicave. 
Apical angle large. Umbones close together. Anterior area only slightly depressed, 
with sharp borders. 

Ornamentation consists of 12 to 15 strong, much elevated ribs with roimded 

1 • Terr. Crut. Ste. Croix' (1869), p. 141. pi dxiv, fig. 3. 



4 CRETACEOUS LA^IELLIBRAKCHIA. 

su mmits, separated by broader rounded hirroTvs. Both ridges and furrows bear 

numerous flattened radial ridges separated by lincai' grooves; the ridges, in 

Avell-proserved specimens, are serrate or granular. At distant intervals a few 

woll-mai'kcd growth-ridges occur. 

Measurements : 

(1) (2) 

Length . 49 . 70 mm. 

Height . 54 . 78 „ 
(1,2) Upper Greensand, Devizes. 

Affinities. — This species is distinguished from L. canalifera (p. 1) by the 
valves being more compressed, the ribs fewer in number, the grooves relatively 
broader, and by the presence of fine radial ornamentation on the ribs and grooves. 

Remarhs. — This appears to be a rare species in England. The specimens from 
Devizes are in the Museum of Practical Geology. The specimen from Humble 
Rocks was collected by Mr. Jukes-Browne, and is now in the Sedgwick Museum. 

Ti/pr. — From the Cenomanian of Coudrecieux, Sarthe. 

Distrlhiitlon. — Upper Greensand (zone of ScJiloenharhia rostra ta) of Devizes. 
Base of Chalk Marl (Bed 10) of Humble Rocks, West of Lyme Regis. 



Lima vectensts, sp. nov. Plate II, figs. 2, a — c. 

'Description. — Shell large, rather compressed, ovate, height greater than length; 
antero-dorsal margin straight, the remainder forming a regular curve. Anterior 
area deeply depressed. Apical angle apparently about 100°. Anteinor ear small; 
posterior ear larger, with a few ribs. 

Ornamentation consists of about 40 rather strong, narrow ribs, with rounded 
summits which, in places, are slightly tubercular. The ribs are closer together on 
the anterior part of the valves than elsewhere. The interspaces are much broader 
than the ril)S, and are flat or slightly concave ; they are marked by numerous fine, 
concentric ridges. 

Afinities. — This species resembles Lima Dujnrdini, Deshayes,^ from the 
Senonian, but the interspaces are flat or nearly flat instead of concave, and the 
well-marked scale-like projections which, in L. Dujardini, are placed at intervals 
on the ribs, l)ut without a concentric arrangement, are not seen. 

1 Dujardin, 'Mem. Soc. guol. de France,' vol. ii (1837), p. 227. pi. xvi, fig. 3. D'Orbignv, 'Terr. 
Crct.,' vol. iii (1847), p. 569, pi. ccccxxvii, figs. 1 — i. 



LIMA. 5 

Bemnrls. — I have seen one example only; it consists of both valves, but with 
the posterior margin imperfect. 

Type. — In the Museum of the Vcntnor Institute. 

Distribution. — Upper Grreensand, chert l)otls (zone of Pecten asper) of tlic Isle 
of Wight. 



LrMA SHBOVAUS, S(mprt)ij, 183G. Plate II, figs. 3, 4a, /*, ba, h, Ga, h, 7a, h. 

1836. Lima ? suBovALis, /. de G. Sowerby. Trans. Greol. Soc, ser. 2, vol. iv, 

pp. 359, 342, pi. xvii, fig. 21. 
1830. — ASPEEA, H. B. Ge'iiiitz. Oliar. cl. Scliicht. u. Petref. des silclis. 

Kreidegeb., pt. 1, p. 23 (pariim). 
? 1847. — SUBOVALIS, A. d'Archiac. Mt'm. Soc. geol. de France, ser. 2, vol. ii, 

p. 309. 

— — OKNATA, A. d'Orhujmj. Pal. Fran9. Terr. Crct., vol. iii, p. 551, 

pi. ccccxxi, figs. 6 — 10. 
1850. — — — Prodr. de Pal., vol. ii, p. 167. 

— — — H. B. Geinitz. Das Quadersandst. oder Kreidegeb. in 

Deutschland, p. 192. 
1867. — — E. Gueranger. Album Pak'ont. de la Sarthe, p. 19, 

pi. xxiv, figs. 7, 12. 

1869. — SUBOVALIS, F. J. Pidet and G. Campiche. Foss. Terr. Crct. Ste. 

Croix (Mater. Pal. Suisse, ser. 5), 
p. 168. 

1870. — OENATA, Pictet and Cavqnche. Ibid., pp. 169, 173. 

1871. Eadula (Acesta) ornata, F. Stoliczka. Palseont. Indica, Cret. Fauna S. 

India, vol. iii, p. 414. 

1872. Lima oenata, H. B. Geinitz. Das Elbtlialgcb. in Sachsen (Palasoutogra- 

pliica, vol. XX, pt. 1), p. 205, pi. xlii, 
figs. 16, 17. 
? 1877. — —A. Peron. Bull. Soc. gi'ol. do France, ser. 3, vol. v, p. 502. 

1877. — Eauliniana, A. J. Jukes-Browne. Quart. Journ. Geol. Soc., vol. 

xxxiii, p. 502, pi. xxi, fig. 2. 
1893. — ornata. R. Michael. Zeitschr. d. doutsch. geol. Gescllscli., vol. xlv, 

p. 234. 

Non 1852. — — A. Buvignicr. Statist, gi'ol., etc., de la Meuse, Atla.'s. p. 23. 

pi. xviii, figs. 17 — 19. 

Bescription. — Shell compressed, ovate or subtrigonal, oblique, consideral)ly 
higher than long, with the ventral and posterior margins rounded. Apical angle 
about 74°. Umlwnes small, close together. Anterior area rather small, dejn-esscd, 
limited hy a ridge, ornamented with ribs separated by broader grooves. 

Ornamentation consists of numerous (C-5 to 70) fairly strong, rounded libs of 



6 CRETACEOUS LA:\IELLIBT{ANCHTA. 

nearly equal size, but sometimes (chiefly near the posterior l)or(l('r) with smaller 
intercalated ribs. The ribs diverge slightly from a nearly median line, and bear 
short spiny or scaly projections at regular intervals but not usually with a con- 
centric arrangement. The spines are rather nearer the inner than the outer side 
of each rib. The gi-ooves are narrow near the umbo but become broader in passing 
ventrally, and at the ventral margin may exceed the ribs in breadth. The grooA-^es 
are rounded and (in some specimens) show transverse ridges. More or less distinct 
"•rowth-lines occur at intervals. 
Mffis^urements : 

(1) (2) (3) (4) (5) (6) 

Length . 25 . 21 . 20 . 17 . 16 . It luni. 
Height . U . 28 . 29 . 23 . 23 . 20 „ 
(1,3) Cambridge Greensand. 

(2) Base of Chalk Marl, Folkestone. 
(4, 5) Upper Greensand, Warminster. 
(G) ,, „ Haldon. 

Affinities. — This species belongs to the same group as the Senonian forms L. 
Dtnikcri, Hagenow,^ and L. muricafa, Goldfuss." It is distinguished from the 
former by its smaller apical angle and by the spines on the ribs being placed more 
closely together. L. muricata differs from L. suhovalis in ha\^ng fewer ribs with 
their ornamentation developed into long scale-like projections, and in having 
oblique grooves in the interspaces. 

Bcmarlcs. — A comparison of the type of Lima mhovalis with examples of L. 
oriKitd leaves no doubt as to their identit)\ The type-specimen of the former is 
somewhat worn, but sufficiently well-preserved for identification, and another 
specimen on the same tablet shows the ornamentation quite clearly ; the shell is not 
silicified, so that it was evidently not obtained from Blackdown — the locality given 
by Fitton — but it has all the appearance of specimens found at AYarminstcr. 

The examples from the Candiridge Greensand were referred to L. UnuUmana, 
d'Orbigny,' by Mr. Jukes-Browne. The interior of these is filled Avith phosphate, 
and the shell, although in some respects well-preserved, is rather abraded, so that 
the remains of the spines usually appear as notches on the inner side (that facing 
the median line) of each rib. The transverse ornamentation in the grooves is often 
very distinct. Mr. Jukes-Browne has recently re-exAmined these specimens and 
agrees with mc in thinking that they cannot be separated from L. svhovaJis. I 

1 ' Neues Jahrl). fiir Miu., etc' (1842), p. 556; Vogel, 'Holliind. Krcide ' (1895), p. 17, pi. i, fiy. 9: 
Ravn, 'Mollusk. Danmarks Kridtaflej.' (1902), p. 100, pi. ii. fig. 14. 

-' ' Petref. Germ.,' vol. ii (1836), p. 89, pi. ciii, fig. 4; Vogel, oj}. cit., p. 17, pi. i, figs. 10, 11. 

' ' Pal. Fran?. Terr. Cn't.,' vol. iii (1847), p. 542, pi. ccccxvii, figs. 5—8; ' Prodr. de Pal.' (1850), 
vol. ii, p. 138; Pictet and Campiche, " Foss. Terr. Cn't. Ste. Croix" ('Mater. Pal. Suisse,' ser. 5, 
1869), p. 154. pi. clxvi, fig. 2. 



LIMA. 7 

have uot beeu able to obtain specimens of i. Rauliniuiui, but it seems to tlil'fer from 
L. mhovalis in having a hirgor posterior ear and in other characters. 

Tijpe>i.—l\\ the Bristol Museum (No. 1778), from the Upper Greensand, proba])]y 
of Warminster. The type of L. ornnta is from the Cenomanian of Le Mans. Tlie 
specimen from the Cambridge Greensand figured by Jukes-Browne is in the 
Sedgwick Museum, Cambridge. 

Distribution. — Upper Greensand (zone of Sc1dujub<(<:hi(i rudynta) of Haldon. 
Upper Greensand (zone of Pecten asper) of North Dorset, and Warminster. Cam- 
bridge Greensand (derived). Rye Hill Sand of Maiden Bradley. Chloritic Marl 
of Rocken End (Isle of Wight). Base of Chalk Marl (Greensand bed) of Folkestone. 
Also recorded by the Geological Survey from the Cenomanian of Devon and Chard. 



Lima scabrissima, sp. nov. Plate II, figs. 8a, b, 9 a, b. 

Description. — Shell compressed, ovate, height greater than lengtli ; autei'u- 
dorsal margin rather short, straight oi' slightly concave, ventral and posterior 
margins forming a regular curve. Anterior area much depressed, sharply limited, 
nearly smooth oi' with faint ribs. Apical angle about 92°. Posterior ear of 
moderate size, with distinct growth-lines ; anterior ear small. 

Ornamentation consists of a large number of narrow, rounded, more or less 
undulating ribs separated by broader grooves. The ribs are generally of nearly 
equal size, but smaller ones may be intei'calated in the grooves. At regular 
intervals the ribs bear scales or lappet-like projections which are arranged con- 
centrically and may become vertical at their ends ; these scales are continued 
across the grooves as laminar projections. On the anterior and posterior ribs the 
" scales " become more pointed. 

Measurements : 

(1) (2) (3) 

Length . 54 . 52 . 38 mm. 

Heiffht .62 . 58 . 42 „ 



'1-1 



(1 — 3) Upper Groonsaiul, Wuruiiiistor. 



Affinities. — This species is near to LiiiM rhotoiiuujensii, d'Orbigny,' from the 
Cenomanian of Rouen, but is distinguished from it by being nuich less convex, by 
having a smaller anterior area and a smaller apical angle, and by the ribs being 
relatively narrower and the grooves broader. 

TyjJes. — In the Museum of Practical Geology. 

Distribution. — Upper Greensand (zone of Pecten as2)er) of Warminster. 

1 'Pal. Franv. Terr. Crct.," vol. iii (18-i7), p. 5.57, pi. coccxxii, tigs. 8—11. 



CRETACEOUS LAMELLIBRANCIIIA. 



Lima asfeka {MaitUil) 1822. Pkitc II, figs. 10, 11 ; riale III, figs. \a,h, 2-4. 

1822. Plagiostoma ? aspeea, G. Mantell. Foss. S. Downs, p. 129, pi. xxvi.fig. 18. 
1854. Lima aspera, /. Morris. Cat. Brit. Foss., ed. 2, p. 170. 

1870. — — F. J. riciet a7id G. Cavqiichc. Foss. Terr. Crct. Sto. Croix 

(Mater. Pal. Suisse, ser. 5), p. 169. 

1871. Kadula (? Acesta) aspeka, F. StoliczJca. Palaeout. ludica, Cret. Fauua S. 

India, vol. iii, p. 41.'). 
1903. Lima aspeea, A. J. Jukes-Browne. Cret. Eocks of Britain (Mem. Geol. 

Survey), vol. iii, p. 450. 

Nou 1830. — — A. GohJ/uss. Petref. Germ., vol. ii, p. 90, pi. civ, fig. 4. 

— 1839. — — H. B. Geinitz. Char. d. Scliicht. u. Petref. des sachs. 

Kreidegeb., pt. 1, p. 23, pi. xxi, fig. 10. 

— 1841. — — F. A. RiJmer. Die Verstein. d. uord-deutsch. Kreidegeb., 

p. 56. 

— 1846. — — A. E. Bkuss. Die Verstein. der bohm. Kreideformat., pt. 2, 

p. 34, pi. xxxviii, fig. 17. 

— 1847. — ~ A. d'Orbujiii/. Pal. Frau^. Terr. Cri't., vol. iii, p. 506, pi. 

ccccxxv, figs. 3—0. 

— 1850. — — — Prod, der Pal., vol. ii, p. 248. 

— — — — A. Alth. Besclu'eib. d. Umgebuug vonLemberg (Haidiuger's 

Naturwiss. Abliandl., vol. iii, pt. 2), p. 243. 

— 1803. — — A. V. Stromheck. Zeitscbr. d. deutsch. geol. Gesellsch.. 

vol. XV, p. 150. 

— 1869. — — E. Favre. Moll. Foss. de la Craie de Lemberg, p. 135. 

— 1870. — — F. J. Pidet and G. Campiche. Foss. Terr. Cret. Ste. Croix 

(Mater. Pal. Suisse, ser. 5), pp. 171, 173. 

— 1877. — — A. Fritsch. Stud, im Gebiete der bohm. Kreideformat. ; II, 

Die Weissenberg. u. Maluitz. Schiclit., p. 132, 
fig. 118. 
_ 1883. — _ _ Ibid., Ill, Die Iserschicht., p. 114. 

— 1887. — —A. Peron. L'Hist. Terr, de Craie (Bull. Soc. Sci. hist, et 

nat. de I'Yonne, ser. 3, vol. xii), p. 150. 

— 1889. — (Plagiostoma) aspeea, 0. Griepenlcerl. Seuou. von Konigslutter 

(Pala;ont. Abhandl., vol. iv), p. 40. 

— 1898. — aspeea, G. Mailer. Mollusk. Untersen. v. Braimschweig u. Ilsede 

(Abhandl. d. k. preussiseh. geol. Landesanst., 
N.F., Heft 25), p. 20, pi. iv, tig. 5. 

— 1900. — — C. Gagel and F. Kaunhowen. Jahrb. d. k. preussiseh. geol. 

Landesanst. fiir 1899, p. 232. 

Description. — Shell ovate, liiglier than long, outline rounded, with the antero- 
dorsal and postero-dorsal margins straightened; convexity small. Umbones small, 
pointed, close together, apical angle 80° to 90''. Anterior urea deep, narrow. 



LIMA. .) 

Anterior ears triaiio-ular, ratlicr small : jinstcrioi- cai's obtusely triaii^iilai', eloiio-ato, 
with radial ribs. 

Valves ornamented with numerous flattened ril)s arranged on eithei' side ol' a 
line passing from the umbo to the ventral margin, fi'om which they diverge sliglitly. 
The ribs are nearly straight or sliglitly undulating, but are often bent abruptly 
where they cross growth-lines. Surface of ribs nearly smooth, l)ut sometimes 
showing very fine concentric ridges or (when worn) ojjlique stria\ On the inner 
edge of each rib — that facing the middle line — there arc short, slit-like indentations, 
above each of which a short spiny projection is seen in perfectly preserved 
specimens. These slits and spines do not, as a rule, show a concentric arrange- 
ment. The grooves separating the ribs are very narrow and are mnvked with 
pits near the umbo and with transverse grooves ventrally. Sometimes near tlie 
margins of the valves new ribs are intercalated or old ones bifurcate. 

Measurements : 





(I) 


(2) 


(.'5) 


(+) 


(5) 


(6) 


(7) 


Length . . . . 


31 


. 30 , 


. 28 , 


. 26 


. 24. 


. 10 , 


1 6 nun. 


Height . . . . 


3G . 


, 33 . 


, 33 . 


, 35 . 


, 26 . 


23 . 


21 „ 


Nuiu])er of I'ibs . 


or. , 


. -il , 


, GO . 


. 4G , 


. 42 , 


, 41 . 


r,2 



(1,2, 3, 7) Totterulioe Stone, Burwell. 

(4) „ „ Cherry Hinton. 

(.5, 6) Chalk Marl, Folkestone. 

Affiuifies. — The Seuonian form figured as Liimt aspcra by Goldfuss, Reuss, and 
Fritsch is clearly distinguished from this species by the chevron-like ornamentation 
on the ribs. Pictet and Campiche suggest that Goldfuss' species may be identical 
with Liu)ii Pin/l-cri, Hagenow,' from Riigen, ])ut this view is not supported by the" 
figures given by Vogel and Ravn. The form figured by d'Orbigny has a larger 
apical angle than L. nspera, Mautell, and does not show the spiny projections on 
one side of the i'il)S. 

The example figured by Reuss" as TAiiki lilana is similai' in form to T,. (iKjtero, 
Mantell, Init does not appear to possess the spiiiy projections on the ril)s. 

Tijpi's. — I have not been able to find the tyjies.'* They came from the ("halk 
Marl of Harasey and Stoncham. 

DisfriliHtian. — Chloritic Marl of Kastbout uc. Chalk Marl of Folkestone, and 
Blue Bell Hill (Bui-ham). 'i'ottei-ulioe Stone of Arlesey, Burwell, Cherry liinton. 
and Stoke Ferry. 

' 'Neues Jalirb. ftir Mm.,' etc. (1842), p. 55G. 

- 'Verstein. bohmisch. Krcidcformat.' (184r)), p. 35, pi. xxxviii, fi<if. 20. 

•'' Tlie name nnjM'ra was used by Chonuiity, (1784) for a recent species of Lima, Init since tliat has 
been sliown to be a synonym of Lima scahra (Born, 1780) there does not appear to be sufficient reason 
for 1,'iviii^' a new niuiic tn tin- Cli:ill< species whicli. for over oiLjhty years, ha.s Won known as T,imn 
asjx'i'". Mantelt 



10 



CEETACEOTS L.\:\IETJJEEAXrTTTA. 



Suh-gC)1llft Pr-AlilOSTOMA, J. So/rfrhij, 181k 

('Mill. Conoli.,' vol. i, j>. 176.) 

IiiM.\ (Pf.AGiosTOMA) suBHiaiDA, Rumcr, 1836. Plate Til, figs. Tx/, Ji, (5 — *.». Text- 
figs. 1, 2, 8. 

1836. Lima subrigida, F. A. Riimer. Verstein. uord-Jcutsch. Oolithen-gcb., p. 79, 

pi. siii, fig. 16. 

— — PLANA, Rimer. Ibid., p. 80, pi. xiii, fig. 18. 

1841. — SUBKIGIDA, Bomer. Die Verstein. cl. uord-deutsch. Kreidegel)., p. 57. 

— — PLANA, El'imer. Ibid., p. 67. 

1877. — suBEiGiDA, (t. JS/i^w. Zeitschr. d. deutscli. gcol. Gesellscli., vol. xxix, 

p. 235. 
1896. — — A. Wollemann. Ibid., vol. xlviii, p. 836. 

1900. — — Wollemann. Die Biv. u. Gastrop. d. deutsch. u. hoUiiiid. 

Neocoms (Abliandl. d. k. preiissich. geol. 

Land.,N.F., pt. :51), p. 30. 




Fia. 1. — Limn {Plagiostoma) suhHgida,'RomQv. C'laxliy Ironstono, Lincolnsliire. Right valve. Natural sizo. 

Sedf^wick Museum, Camliridgc. 

Description. — Shell convex, oval, height sliglitly greater th;iii length ; initcro- 
dorsal margin nearly straight, postcro-doi'.^nl inucli sliortcr and nearly straight, tlic 
remainder ronnded and forminor a regular curve. Ai)ical aiiirle rather more than a 



LIMA. 



11 



right uiigle. Uml)ones of moderate size. Area large, with a hirge triangular 
ligament pit near the middle but bending posteriorly. Anterior area large, deeply 
depressed, especially near the ears. Ears rather large, the anterior triangular, the 
posterior rather larger, more elongate ; surface with growth-lamellae only. 

Surface ornamented witli numerous (43 to 52) radial ribs, which are straight or 
slightly undulating. The ribs are flattened; near the uml)o they are separated by 
Tuxrrow grooves, but in passing ventrally the grooves increase in width and become 
as wide as or wider than the ribs. The grooves are rather shallow and rounded. 
The anterior and posterior ribs are narrower than the others. Near the umbo the 
grooves are punctate, but in passing ventrally the pits soon become replaced by 




Fio. 2. — Lima {Plaijiostoma) subrigida, Romor. C'laxby Ii-onstono, lionuiwortli Haven. Right valve. 

Natural size. Sedgwick Museum. 

transverse furrows separated by ridges, and the latter may pass on to the ribs. 
the anterior area ribs are small or absent, but growth-lines are usually distinct. 
Measurements : 

(1) (2) (3) 

Kt'.i 100 80 

111 1 08 85 

— (J3 — 

48 49 48 



On 



Length 
Height 
Thickness 
Number of riljs 



(i) 


(5) 


Ci) 


(7) 


(8) 


(9) 


73 


72 


ill 


()3 


38 


31 mm. 


79 


7i; 


()5 


05 


30 


40 „ 


51 


k; 


1-3 


ol) 
52 


52 


44 



(1 — 9) Claxhy IroustoiK', Beuuiworth Haveu. 

Affinities. — L. rii/nrnlriisis, Pictet and Campiche,' is distinguished from 
L. subrigida by its more (luadrilateral outline, more luunerous ril)s and finer 
> 'Ton-. Civt. Ste. Croix' (1869), p. 138, \A. clxii, fiijs. 5—8. 



12 CRKTACEOUS l,AMKi;iJRRAN(M[T.\. 

grooves, ami alsij liy the eai'liiT part of the sliell heiiii;' nearly sinoutli. //. mihcr- 
soneusis, Pictet and Caiii]iiclR',' is relatively longer and has narrower grooves. 

Remarks. — On account of the imperfect figures of L. s/iliriijiiln niven by Romer, 
the English specimens have not hitherto been referred to that species; they agree 
perfectly with the descriptions except in the number of ribs, but Dr. Wollemanii 
informs nie that that character is variable. 1 have sent a specimen from the 
(Jlaxby Ironstone to Dr. AVollemann, and he is able to confirm my identification of 
the species. Specimens from the Spoeton Clay ilit'fei' from those found in Liueuln- 
shire in haviiii;- fewer i'il)s w itli relatively fewer grooves, but since this is a very 
variable character it cannot be regarded as indicative of more than a local variet}-. 




Fill. ;i.— iimri (I'Uujiosloma) subri<jida, Kiimor. Claxby Ironstoui!, Buuuiwurth Uiivuu. Arua of ri^'lit 

valve. X |. Sedgwick Museum. 

Ti/jir.'i. — Fi'om the Ililstlion of Hrunswiek. 

Ihslriliiiflmi. — Cla.\1)y Ironstone (zone of Ih'lcianitcs Idteralts) of iJenuiwortli 
Haven. Upper |)art of the SiJeeton Clay of Speeton. 



Lima (I^.aciostoma), sp. cf. Okukjnya.va, MutluToii, 181-2. Plate III, figs. 10, n — c. 

1812. Lima Ukbignyana, P. Mullwron. Cat. Foss. dcs. Bouclies-du-Rhone, p. 182, 

pi. xxi.\, fij,'s. 3, 4. 

1846. — — A. d'Orbiijiuj. Pal. Frauy. Terr. Cn't., vol. iii, p. 530, 

pi. ccccxv, figs. 1 — 4. 

1860. — — d'Orhhjnij. Prodr. do Pal., vol, ii, p. lU7. 

18.55. — — G. Cotteau. Moll. Foss. de rVoiiue, y. lUU. 

1865. — — H. Coqitand. Mou. Aptk-ii do rFsjia','!!!', p. IlK. 

1866. -^ — P. de Loriol. Foss. O.^litli. Corall. V-aliiw^. ct Vf^«n. 

Mt. SuIlvo, p. 82, pi. D, fii^r. 13. 

1867. — — de Luriul, iu Favrc. liecL. ycol. Saus Savoie, vol. i, 

p. 387, pi. C, fiy. 24. 
1869. — — F. J. I'ictfl and G. Campiche. Foss. Terr. Crct. Ste. 

Oroi,\ (Mater. Pal. Suisse, ser. 6), 
p. 126, pi. cLxi, fiy. 4. 
1871. IvADULA (Acesta) Obbionyana, F. SluiiczJca. PalaDout. Indica, Cret. Fauua 

S. ludia, vol. iii, p. 414. 

1 Loc. cit., p. 140, i>I. clxiv, figs. 1, 2. 



LIMA. 13 

Description. — Sliell moderately convex, oval, liit^licr than long, venti-al and 
posterior margin rounded. Umbone.s sharp. Apical angle about 80°. Anterior 
area depressed, limited by a rounded edge, ornamented with riljs. Ears with 
distinct growth-ridges. Posterior ear higher than hnig, and larger than the 
anterior ear. 

Ornamentation consists of about 52 flattened ribs, slightly undulating, 
separated by very nari-ow grooves Avitli pits. Near the ventral margin the ribs 
become divided by a median groove. Near the anterior and posterior margins 
the ribs are rather narrower than elsewhere. A few moderately distinct growth- 
lines occur. 

Measurements : 

Length .... 20 mm. 

Height .... 25-5 „ 

-Ufiiiitics. — This is distinguished from L. rillerseiisis (see below) by its more 
numerous and narrower ribs. 

Remark. — I have seen one specimen only, which is preserved in the British 
Museum, No. L 157-ji. 

Didrihnfiiiii. — Lower Greensand (Ferruginous Sands) of Shanklin. 



LiM.v (Plagiostojia) viLLiousKNsis? I'ictct uiul Cuiiijuclu', 18G'J. i'lale ill, ligs. Ihi, 

Ul>,l2<i,b,r3. 

? 1869. Lima villersensis, F. J. Pictet and G. Campiche. Foss. Terr. Crt't. Ste. 

Croix (Mati'r. Pal. Suisse, ser. 5), 
pp. 127, 162, pi. clxi, fig. 5. 

Description. — Shell moderately convex, oval, higher than long, ventral and 
posterior margins rounded. Umbones sharp. Apical angle about 8-5°. Anterior 
area depressed, bounded by a sharp edge. Posterior ear larger than the anterior, 
higher than long, with the outer angle obtuse, and with a few radial ribs. 

Ui'nameutation consists of from o2 to ^G broad, flattened, nearly straight ribs, 
separated by linear grooves with distinct pits. Near the anterior, and sometimes 
near the posterior border, the riljs l)econie narrower. A few well-marked growth- 
ridges may occur at distant intervals. Near the ventral mai-gin of the valves 
(ventral to a growth-ridge) the position of the ribs is sometimes slightly shifted, 
and the number of ribs may increase owing to the fission of some. 

Measurements : 

(1) (2) (3) (4) 

Length . 20 . 10 . 18 . II nun. 

Height . 2G-.J . 2.5 22 . 17 „ 

(1 — 4) Lower GreeusauJ, i'ariugJou. 



II CRETACEOUS LAMELT.TBK.WCTTT A. 

Affinilu's. — I have seen only a few examples of this form. They agree witli 
L. viUerseims except in having a rather smaller apical angle. In this respect they 
resemble L. Orhifjnydna, Matheron (see above), but tliey differ from that species in 
possessing fewer and straighter ribs. I have not seen any undoubted example of 
L. vUlcrscniyis and am nnal)lc to state whether the apical angle is constantly larger 
than in the English si)ecimens. Pictet and Campiche say that it is about 95°, but 
the specimen they figure possesses an apical angle of 90° only. In the English 
specimens it is about 85°. 

This is the form which was referred by Sharpe^ to L. coiisoliriim, d'Orbiguy, 
but it possesses considerably fewer riljs than that species. 

Ti/pe. — L. villersemk is found in the Valanginian of Ste. Croix. 

Dlddbidion. — Lower Greensand of Fariugdon. 



Lima (1'i,A(J1u,stu.ma) tiKmoii^xiWjifOjiiiyiiij, lb 1-7. Plate III, figs. 11, 15, 10",//. 

Plate IV, fig. 1. 

1847. Lima semioenata, A. d'Orhujuy. Pal. Fran9. Terr. Crct., vol. iii, p. 555, 

pi. ccccxxii, figs. 1 — 3. 
1850. — — d'Orhlijnij. Prodr. de Pal, vol. ii, p. 167. 

18(37. — — E. Gue'raiujer. Album Pak'out. de la Sartlio, p. 19, 

pi. xxiv, &g. 13. 

1870. — — F. J. Fidel and G. Campiche. Foss. Terr. Crt't. Ste. 

Croix (Mater. Pal. Suisse, ser. 6), 
p. 169. 

1871. Radula (Plagiostoma) semioenata, F. Stoliczka. Palseout. ludica, Cret. 

Fauna S. India, vol. iii, p. 414. 
? 1885. — — — F. Niitling. Die Fauna d. Laltisch. 

Cenomau. (PalsBont. Abhandl., 
vol. ii), p. 15, pi. ii, fig. 4. 

description. — Shell compressed, rounded, lieight and length nearly equal. 
Antei'o-dorsal border straight or slightly concave. Umbones close together. 
Anterior area depressed, with a sharp edge. Apical angle 120°. 

Surface nearly smooth, shiny, with numerous, very fine, regular, concentric 
linear ridges, and with radial punctate grooves near the umbo and near the 
anterior and posterior margins. The grooves near the anterior margin are fewer 
and more widely separated than those near the posterior margin. 

' ' Quai-t. Jouru. Geol. Soc.,' vol. x (1853), p. 193 (snh-consobrina, d'Orbigny, 'Prodr. de Palcont.,' 
(1850), p. 167). 



LIMA. 



15 



Mensnrcmrrifs 



Length 
Height 



(5) 

23 mill. 
23 „ 



(1) (2) (3) (4) 

32 . 31 . 29 . 29 . 

33 . 32 . 29 . 26 
(1, 2) Upper Grecnsand, Potterne. 

(3, 5) „ „ Ventnor. 

(4) „ „ Blackdown. 

Affi.nitics. — This species is distinguished by its compressed valves and rouiulcd 
outline. 

Tijpe. — From the Cenomaniau of Le Mans. 

Distribution. — Upper Greensand (zone of Schlmnhachia rostniln) of Potterne 
(Devizes) and Blackdown. LTpper Greensand (zone of Feet en asper) of Ventnor. 
Chalk ]\Iarl of Folkestone. 



Lima (Plagiostoma) Meteri, sp. nov. Plate IV, figs. 2,3. Text-fig. 4. 

1896. Lima simplex, A. J. Jukes-Browne. Quart. Joum. Geol. Soc, vol. lii, p. 162. 

Description. — Shell ovate or subtrigonal, much compressed, a little higher than 
long, oblique, considerably inequilateral ; antero-dorsal margin long and 




Fio. 4. — Lima (Plagiostoma) Meyeri, sp. nov. Upper Greensand, Warminster. Museum of Practical Gcologj-, 
No. 8838. Left valve and antero-dorsal view. Natural size. 

straightened, ventral and postero-ventral margins rounded. Umbones small, close 
together. Ajiical angle from 90° to 100°. Anterior area depressed, long and 
narrow, with a few radial 7-il)s and vertical grooves. Posterior ear small ; anterior 
ear not seen. 

Ornamentation consists of narrow, linear, .-^hallow, pitted grooves wliieli may 



(3) 


(4) 


(5) 


48 


42 , 


34 mm 


52 


47 . 


37 „ 



16 CRETACEOUS LAMELTJBR AXCTITA. 

be confined to tlio anterior and posterioi- ])arts of the valves or ina_y extend over 
the whole surface. The grooves are soniewliat irreG^nlar aiid tlie interspaces are 
broad and flattened. At distant intervals a few well-inarked Ljrowtli-riniifs occnr, 
l)cyond -which, in some cases, the iil)s cease. 
Arf'anirrrmfvfs : 

(I) (2) 

Length . (\9 . 53 

Height . 71 . 5G 

(1 — .5) Uppov GrociisaiKl, Wariiiiiistor. 

Affivifici. — This species differs from Li'ma armhivuKfn (p. 1 1) in lieing larger, 
relatively higher, more trigonal in outline, and in having tlie I'adial grooves nmi'c 
extensively developed. It is distingnisheil fi'oni Lhiiit sin/jih-.r, (l"()i'l)igny,' in 
being nnicli less convex, in the height being relativel}' less, the antei-o-dorsal 
margin shorter, the anterior area smaller, and the anterior grooves less })rominent. 

The shell is relatively longer and the apical angle larger than in L. siiJi-rnvfto- 
Iniiiii, d'Orbigny." It is also relatively longer, Avith a longer antero-dorsul nuirgin 
and the radial grooves less well developed, than in L. nrtumi (p. 22). 

Tijix'n. — From Warminster. In the Museum of Practical Geology. 

Dinfribitfinn. — Upper Grecnsand (zone of Ppc/pu asppr) of Warminster. Eye 
Hill Sands and Chloritic Marl of Maiden Bradley. Cennmaninn flMeyer's Beds 10 
and 11) of Hooken and Dunscombe (Devon coast). 



liLMA (l'l..\i;insTnMA) (il.olinSA {Si)irri-h//), \H'A(>. I'llltc I \\ flgS. 4w^ — C, hilji, i't (I — C. 

183G. LuciNA? Gi.oBosA, J. (}(' C. Sowrhi/. Tiaus. GphI. Soe., ser. 2, vol. iv, 

p. 335, pi. xi, fig. 2 (non Lucimi 
ylohosa, Riimer, 1839). 

1854. Lima (iLODosA. J. Morris. Cat. Brit. Foss., ed. 2, p. 171. 

1895. — — E. Tiessen. Zeitschr. iI.t dcuts.li. l;oi.1. Oosfllsili., v..l 

.\lvii, ]). 473. 

Descrijitioii. — Shell very convex, of moderate size, oval, length considei'ably 
greater than height, outline rounded with the nntero-dorsal margin long and 
straightened. Umbones incurved, bhint. Apical angle al)out 11S\ Anterioi' 
area large, very deep, limited by a sharj) edge, with ratUal i-ibs. Ears small. 

S\irface of v.alves polished, with faintly-marked growth-lines at intervals; 

' 'Pal. Fi-au^. Terr. Crct.,' vol. iii (1847), p. 545, pi. ccccxviii, fijrs. 6—7. 

- Il)id., p. 55G, pi. ccccxxii, figs. 4 — 7; L. »uh-consohrinii, d"Orl)igny, ' Prodr. de Palcont.,' vol. ii 
(1850), p. 167. 



LIMA. 17 

ornamented with numerous pits having a regular radial and concentric arrange- 
ment and giving rise (in some cases) to the appearance of slightly-raised radial 
and concentric ribs. Near the ventral margin the pits become more elongated 
(parallel with the margin) and their concentric arrangement may become wavy or 
irregular. At the anterior and posterior margins the radial arrangement is often 
more distinct than elsewhere. Sometimes on the median ])art of the valve the 
concentric arrangement alone can be recognised. 
Measurements : 

(1) (2) (3) (i) (5) 

Lent^th . 31 . 27 . 25 . 24 . 22 



«^) 


(7) 


(H) 


20 . 


18 , 


12 mm. 


17 , 


, K) , 


. 10 „ 



Height . 25 . 23 . 21 . 21 . 19 

(1—3, 5, 7, 8) Tottemhoe Stoue, Bunvell. 
(4) Chalk Marl, Veutuor. 
(6) ,, ,, Clevancy. 

Affinities. — This species closely resembles Lima albensis, d'Orbigny/ from the 
Gault of Ervy (Aube), Macheromenil (Ardennes), the Perte-du-Rhone, etc. I have 
not seen any specimens of L. albent^ls, but it appears to differ from //. glfiljosa in the 
absence of the punctate ornamentation and in having a smaller apical angle. 

L. (jlohosa is distinguished from L. Hoperl (see below) by its smaller size, more 
intiated valves, and by the close-set rows of radial and concentric pits. 

Type. — In the Museum of the Geological Society, No. 1538, from the Chloritic 
Marl of the Isle of Wight. 

Distribution. — Gault of Folkestone. Red Limestone of Ilunstaaiton. Upper 
Greensand of Warminster. Cambridge Greensand (base of Chalk Marl). Chalk 
Marl of Ventnor, Clevancy, Chilcomb well (Winchester), Burham, Folkestone and 
Cherry Hinton. Cenomanian of Wilmington. Totternlioe Stone of Burwell. 
Zone of H. subylobosus of Chilcomb and Fulbourn. 



Lima (Plagiostoma) lloi'uui, Mantell, 1822. Plate IV, figs. 7, Sa, l>, \hi, l>, 10, 

11((, /;, 12a, b. 

1822. Plagiostoma Hopeei, G. Mantell. Foss. S. Dowus, p. 20-i. pi. xxvi. 

figs. 2, 3. 15. 
— _ — /. de €■ Sowerhij. Min. Couch., vol. iv, p. ill. 

pi. ccckxx. 



1 'Pal. Fran?. Terr. Crct.,' vol. iii (1847), p. 541, pi. cceexvi, figs. 1-5, IG ; ' Prodr. de Palcont.,' 
vol. ii (1850), p. 138 ; Pictet aud Roux, ' Moll. Foss. Grcs verts de Geuivc ' (1852), p. 488, pi. xl, 
tig. 9; Pictet aud Campiche, " Poss. Terr. Crct. Ste. Croix" (' Mat^'r. Pal. Suisse.' ser. 5. 18(3'.'). 

p. 160. 

o 



18 CRETAGEOUS LAMELLIBRANCHIA. 

1822. Plagiostoma Mantelli, A. Brongniart. Descript. gcol. euvir. de Paris. 

In Cuviers Ossem. Foss., vol.ii, 
pt. 2, p. GOO, pi. iv, fig. 3. 
1825. Pachytos Hopeei, M. J. L. Defmnce. Diet. Sci. nat., vol. xxxvii, p. 207. 
1827. Plagiostoma punctatum, S. Nilsson. Petrif. Suecana, p. 24, pi. ix, fig. 1. 
1832. Lima Hopeei, G. P. Deshayes. Iii J. G. Bnujuirre, Hist. nat. des Vers et 

des Moll. (Eucyc. lUL'thod.), vol. ii,p. 349. 

1836. — Mantellii, A. Goldfuss. Petref. Grerm., vol. ii, p. 92, pi. civ, fig. 9. 

— — HoPEKi, Goldfuss. Ibid., p. 91, pi. civ, fig. 8. 

— — — Lamarck. Aniiii. saus Vert. (ed. 2 by Deshayes and Milne- 

Edwards), vol. vii, p. 120. 

1837. Plagiostoma punctatum, W. Hisinger. Lethsea Suecica, p. 54 {not pi. xv. 

fig. 3). 

1838. Lima Hopeei, H. G. Bronn. Lethsea Geognost., vol. ii, p. 682, pi. xxxii, fig. 8. 

1839. — — H. B. Geinitz. Char. d. Schicht. u. Petref. des siichs. 

Kreidegeb., pt. 1, p. 24 {? parti m). 

1841. — 'HahtbIiIjU, F. A. Earner. Die Versteiu. d. uord-deutsch. Kreidegeb., 

p. 58. 

— — Hopeei, Bomer. Ibid., p. 58. 

— — NiLSSONi, Burner. Ibid., p. 57. 

1842. — GoLDFUssi, F. v. Hagenow. Neues Juhrb. fiir Miu., etc., p. 555. 

? 1846. — Mantelli, H. B. Geinitz. Grundr. d. Versteiu., p. 472, pi. xx, fig. 13. 

— — Hopeei, Geinitz. Ibid., p. 473, pi. xx, fig. 14. 

— — — A. E. Beuss. Die Versteiu. der bohm. Kreidefomiat., pt. 2, 

p. 34, pi. xxxviii, figs. 11, 12. 
1847. — So-wvu-DYi, J. Mailer. Petref. der Aachen. Kreidef., pt. 2, p. 67. 
1850. — Hopeei, H. B. Geinitz. Das Quadersaudst. oder Kreidegeb. iu 

Deutschland, p. 192. 

— — SowEEBYi, Geinitz. Ibid., p. 192. 

— — Hopeei, A. Alth. Geogn.-jialaiont. Beschreib. von Lemborg (Haidiu- 

ger's Naturwiss. Abhandl., vol. iii, pt. 2), p. 240. 
? — — Mantelli, Ii. Kiier. Verstein. v. Lemberg (Haicliuger"s Natur- 

wissensch. Abhandl., vol. iii, pt. 2), p. 29. 
Plagiostoma Hopeei, var., /. de 0. Sowerhj, in F. Dixun. Geol. Sussex, 

pp. 348, 356 (p. 383, ed. 2), 
pi. xxviii, fig. 21. 
1851-2. Lima Soweebyi, H. G. Bronn. Lethsea Geogn., ed. 3, vol. ii, pt. 5, p. 278, 

pi. xxxii, fig. 8. 
? 1852. — Hopeei, R. Kner. Deukschr. d. k. Akad. d. Wissensch. Wieu, Math.- 

nat. CI., vol. iii, p. 318. 
1854. — — J.Morris. Cat. Brit. Foss., ed. 2, p. 171 (^«n-/(«0. 
1863. — — S. Placketko. Das Becken von Lemberg (Jahresber. d. k. k. 

zweit. Ober-gymuas. iu Lemberg, 1863). p. I'.t. 

— — — A. von Slrombeck. Zeitsohr. d. deutsch. geol. Gesellsch., 

vol. xv, p. 148. 

— — — B. Drescher. Ibid., p. 355. 

1869. -■ - E. Favre. Moll. Foss. de la Craie de Lemberg, p. 137, 

pi. xii. fig. 19. 



LIMA. 19 

1870. Lima Hoperi, F. Eiimer. Geol. von Oterscliles., p. 315, pi. xxxiv, R^. 10. 

— — —F.J. Fidel and G. Caminche. Foss. Ten-. Crct. Sfo. Croix 

(Mati'r Pal. Suisse, ser. 5), 
pp. 171, 173. 

— — SowEKBYi, Pictet and Campiche. Ibid., p. 173. 

187'2. — — H. B. Geinitz. Das Elbtlialgeb. in Sachscn (Palaeonto- 

graphica, vol. xx, pt. 2), p. 41, pi. ix, 
figs. 13, 14. 

1877. — — A. Frit sell. Stud, im Gebiete dev bijlini. Kreideformat. : 

II, Weissenberg. u. Malnitz. Schicht., 
p. 133, fig. 120. 

1882. — HoPEEi, H. Schrikler. Zeitsclir. der deiitsch. geol. Gesellsch., vol. 

xxxiv, p. 263. 

1883. — SowEEBTi, A. Fritsch. Stud, im Gebiete der l)61iin. Kreideformat.: 

III, Iserscbiclit., p. 115, fig. 87. 

1888. — HoPEEi, ^. Pew). L'Hist. Terr, de Craie, p. 149. 

1889. — (Plagiostoma) Hopeki. 0. Griepenkerl. Senon. v. Ktinigslutter 

(Palseont. Abliaudl., vol. iv), 
p. 40. 

— — HopEKi, A. Fritsch. Stud, im Gebiete der biihm. Kreideformat.: 

IV, Teplitz. Seliiclit., p. 84, fig. 78. 

— — — E. Hohapfel. Die Mollusk. Aaclien. Kreide (Palaeontogra- 

pliica, vol. xxxv), p. 240, pi. xxvii, fig. 5. 

1892. — (Plagicstoma) Hopeei, E. Stolley. Die Kreide Sehleswig-Holsteins 

(Mittbeil. a. d. Mineralog. Instit. 
Univ. Kiel, vol. i), p. 237. 

1893. — HopERT, A. Frit. fcJi. Stud, im Gebiete der bohm. Kreideformat. : V, 

Priesener Schicht., p. 100. 

1894. — — B. Lundgren. Mollusk. i MammiUatus- ocli Miicronata- 

zonerna (K. Svenska Vet. Akad. Handl. 
N. F., vol. sxvi, No. G), p. 42. 

1897. — — B. Leonhard. Kreideformat. in Olierschles. (Palaconto- 

graphica, vol. xliv), p. 46. 

— — — A. Hetinifj. Eevis. Lamellibr. i Nilsson's ' Petrifie. Suecana,' 

(K. Fysiogr. Siillsk. i Lund. Handl., N. F., 
vol. viii), p. 30, pi. ii, fig. 13. 

— — (Plagiostoma) Hoperi, H. Woods. Quart. Journ. Geol. Soc, vol. liii, 

p. 383. 

1898. — Hopeki, G. Miiller. Mollusk. Untersen. v. Braunschweig u. Ilsede, 

p. 24, pi. iv, fig. 1-2. 

1901. — — A. Wollemann. Jahrb. d. k. preussisch. geol. Landesanst. 

fiir 1900, vol. xxi, p. 15. 

1902. — — A. WoUemann. Liineburg. Kreide (Abhandl. d. k. preussisch. 

geol. Landesanst., N. F., Heft 37), p. 58. 

_. — J. P. J. Ram. Mollusk. Danmarks Kridtaflej. : I, Lamellibr. 

(K. Danske Vid. Selsk. Skrift. 6 Rtekko, 
nat. og math. Afd., vol. xi), p. 99, pi. ii 
fit;. 18. 



20 CRETACEOUS LAMELLIBRANCHIA. 

Non 1847. — — A. iT Orhiyny. Pal. Franc. TeiT. Cret., vol. iii, p. .'JC4, pi. 

ccccxxiv, figs. 10 — 13. 
1847. — Mantelli, (VOrhigny. Ibid., p. 568, pi. ccccxxvi, figs. 3 — 5. 

— 18-50. — HoPEEi, d'Orhujny. Prodr. de Pal., vol. ii, p. 248. 

— — — Mantelli, cTOrhigny. Ibid., p. 248. 

1877. — HopERi, A. FritscJi. Stud, im Gebiete der bijhm. Kreideformat. : 

II, Weisseuberg. u. Malnitz. Schielit., p. 134, 
fig. 121. 

— — — Mantelli, Fritsch. Ibid., p. 134, fig. 122. 

— 1872. — HoPEEi, H. B. Gcinitz. Das Elbthalg<>l>. in SacLsen (Palaonto- 

graphica, vol. xx, pt. 2), p. 40, pi. ix, 
figs. 11, 12. 

— 1881. — — J- Kiesow. Cenomanversteiu. a. d. Diluvium d. Umgeg. 

Danzig's (Schrift d. naturf. Gesellseb. in 
Danzig, N. P., vol. v), p. 414, figs. 9, 10. 
? — 1893. — sp., cf. HopERi, B. Michael Zeitschr. d. deutscb. geol. Gesellsch., 

vol. xlv, p. 234. 

Descrijitiou. — Shell convex, oval, rounded, considerably inequilateral, longer 
tlian high. Antero-dorsal margin rather long, slightly convex or nearly straight ; 
postero-dorsal margin rather short ; the remainder forming a regular curve. 
Umbones close together. Apical angle 115° to 117°. Ears rather small, with 
growth-lines; the posterior longer than high and larger than the anterior ear. 
Anterior area large, deep, with a more or less sharp border, often with radial 
grooves which vary in number and are more distinct near the umbo than 
anteriorly. 

Surface of shell nearly smooth. In the region of the umbo numerous linear 
grooves with pits occur ; these may also extend on to the anterior and posterior 
parts of the shell, and in some cases they are present on the middle of shell, 
reaching a part of the way or even quite to the ventral margin. The grooves are 
slightly wavy, sometimes discontinuous, and are deeper near the anterior and 
posterior margins, and often more widely separated near the former. 'New 
grooves are introduced at various distances from the umbo. 

Measurements : 

(1) (2) (3) (4) (5) (6) 

Length 57 57 56 52 51 51 
Height 52 50 52 50 47 40 

(1) M. cor-anguimini zone, Graveseiid. 

(2) Uintacrinus band, Devizes Road, 

Salisbury. 
(3, 6, 12) A. quadratus zone. East Harnbam. 
(4, 7) M. cor-anguinum zone, Gravesend. 



(7) 


(8) 


(9) 


(10) 


(11) 


(12) 


47 


41 


37 


34 


31 


31 mm. 


42 


39 


32 


32 


28 


26 „ 



(.5, 10) M. cor-anguinum zone, Northflcet. 
(8) Chalk Rock, Underwood Hull, Dulliii 
bam. 
(9, 11) B. mucronata zone, Norwich. 



Affinities. — This species was described by Brongniart under the name ri(i<jios- 
tnnia Miiiif'-lli from spccimeTis wliich wore sent to him by Mantcll from near 



LIMA. 21 

Brighton— probablj' from Lewes. Maiitell ' regarded Plafiiostoma Mtintelli as a, 
synonym of his riat/iosfomn Ifupi'n, and I think there can lie no doubt as to the 
correctness of that view. 

Geinitz (1872) considered Lima Hoperi of Sowerby to be distinct fromL. lloperi 
of Mantell, thinking that the former (which he named L. Son-erbi/i) was distinguished 
by being almost smooth, whereas the latter is covered with radial grooves. The 
smooth and the gi'ooved forms agree exactly in shape, and between these extremes 
in ornamentation every gradation may be seen. Moreover, although one of the 
specimens figured by Mantell (fig. 3) is ornamented all over, the others (figs. 2, 1 5) 
possess grooves on the sides only. I think, therefore, that there can be no doubt as 
to the identity of L. Hoperi of Sowerby and L. Ilopori of Mantell. Further, it 
should be noted that Sowerby's specimens were sent to him by ]\Iantcll as examples 
of his L. Hopori. 

The specimens figured h\ Geinitz (1872) as L. Ilopcri (from the Pliiner-kalk of 
Strehlen) are relatively higher (especially fig. 11) than Mant ell's species, and are 
probably examples of L. crefacm (see below). 

L. Ropcrl of d'Orbigny- differs in having a smaller apical angle, in being 
relatively higher, much compressed, and with the grooves more widely separated. 
It may, however, be only a variety of L. Hoperi, Mantell. I have seen undoubted 
examples of L. Hoperi, Mantell, from the Senonian of Marromme (near Rouen), 
Lillebonne (Seine-Inferieure), and from other French localities. The form de- 
scribed and figured l)y d'Orbigny as L. MantcJU is referred to below (p. 2o). 

L. Lamberti of Peron,' fi'om the zone of Micraster breviporus of Joigny, may be 
only a variety of L. Hoperi. It is stated to diifer chiefl}' in its greater length, but 
in this respect it can, I think, be matched by some undoubted varieties of L. 
Hoperi. 

For the relation of L. Hoperi to Z. ijlobosa see page 17, and to L. cretacea 
see page 23. 

Bemarhs. — This species varies considerably in the extent of the ornamentation. 
Some examples are smooth, save for the pitted grooves near the umbo ; in many 
cases the grooves are continued on to the sides of the sliell ; less frequently they 
extend to the middle of the valve, and may even reach the ventral margin. I 
have not seen sufficient examples, of which the exact liorizons are known, to enable 
me to determine whether any of the varieties are characteristic of certain zones. 

Types. — I have not seen the types. The specimens figured by Sowerby are in 
the British Museum. The types, and also Sowerby's specimens, came from the 
Upper Chalk (probably from the zone of Micraster cor-testudinarium or the zone of 

• 'Trans. Geol. Soc.,' ser. 2, vol. iii (1835). p. 206. 

"- See Jukes-Browne, 'Quart. Jouru. Geol. Soc..' vol. Iii fl89(!). p. 152. 

8 ' Hist. Terr. <!»> Craie ' (1888), p. 151. pi. ii. fi.,'. 1. 



22 CRETACEOUS LAJVIELLIBRAKCHIA. 

M. cor-mujuimim) near Lewes. An example from Cambrai is in the d'Orbigny 
Collection at Paris, but it is probably not the specimen figured in the ' Palcontologie 
Fran^aise.' 

Disfrihnfidii. — (i) Zone of Tcrehraiulina of Bevendean, near Brighton.' 

(ii) Zniip of IfoJiisfrr pltiinis- of AVinehester, Lewes, Dovei', Kcnl(>y, Ciixton. 
Chalk Rock of Boxnioor, Luton, Underwood Hall (DuUinghani), Westley 
Waterless. 

(iii) Zone of Micrastrr (■(>r-lc-'<fii(liii«(rivm of Lewes, Dover, Purley, Strood, 
Chatham, Swaffham- (Norfolk). 

(iv) Zone of Micr<nter cor-anr/uimnn of Winchester, Porton, AVitherington, 
Qnidhampton, Lewes, the Sussex coast, St. Margaret's, Gravesend, Northflect, 
Hailing Pit (South Croydon). 

(v) Zone of Marsupifcs tefffndwariiis of the coasts of Sussex, Thanct, and 
Yorkshire. T^iutacniiiis hnml of Devizes Road, Salisbury. 

(vi) Zone of Arfiuocamax <jii<nhrihii< of East Harnham, Hurslcy (Winchester), 
the coasts of Sussex and Yorkshire. 

(vii) Zone of Bi-lmniifiila mvcrovafa of the Dorset coast and Norwich. 

(viii) ('lialk of Trimingham. 



JiiMA (Pi.a(!I(»stiima) ciiKTACEA, uoiu. uov. Plate IV, figs. 13, 14 (I — r', 15. Plate V, 

figs. \(i,h, 2, o, A«,h. 

? 1847. Lima Mantei.i.ii, A. (VOrhujnu. V-A. Fraii9. Terr. Crt't., vol. iii, ji. 508, 

pi. ccccxxvi, figs. 3 — 5 (uou L. Man- 
telli, Brongniart). 

V 1850. — — — Prodr. de Pal, vol. ii, p. 248. 

— — L.s:viuscuLA, J. de C. Sowcrhy, in F. Dixon. Geol. Sussex, p. 347 

(p. 382, ed. 2), pi. xxviii, fig. 14, 
(uou L. Ireviuscvla, Sovcerby, 
1822). 
y 1872. — HorEKi, H. B. Geinitz. Das Elbthalgeb. iu Sachseu (Palaeontogra- 

jilupa, vol. XX, pt. 2), p. 40, pi. ix, figs. 11,12. 
? 1877. — — A. Frxtsch. Stud, iiu Gebiete der buhm. Kreidoformat. : II, 

Weisseuberg. u. Malnitz. Schicht., p. 134, 
fig. 121. 

V — — Mantelli, Fritscli. Ibid., p. 134, fig. 122. 

? 1888. — — A. Peroii. L'Hist. du Terr, de Craie, p. 151. 

Description. — Shell of small convexity, oval, very inequilateral, higher than long. 

Antero- and postero-dorsal margins nearly straight, the remainder forming a 

' Also recorded from the Terebraiulina zone of South Dorset by Dr. Barrois. 
- This may bo from the M. cor-anguinnm zone. 



LIMA. 23 



regular curve. Unibones small, cloric together. Apical angle usually about 1(30°, 
but sometimes only 90°. Ears small, the posterior larger than the anterior. 
Anterior area of moderate size, very deep, with a sharp edge and numerous radial 
ribs. 

Ornamentation consists of numerous, well-defined, radial grooves with distinct 
pits, covering the entire surface of the shell. The grooves are straight or slightly 
wavy, and in some cases are linear, in others broader, the latter giving the appear- 
ance of flattened or rounded ribs to the interspaces. The pits in the grooves some- 
times extend into the sides of the ribs. New grooves may be introduced near the 
ventral margin or occasionally near the middle of the valve. In well-preserved 
specimens very fine concentric ridges are sometimes seen. A few gi'owth-rings 
are usually present. 

Meatmrcmeids : 

(fi) (V) (8) (9) 

17 K) 12 11 mm. 
lU 10 14 12 „ 

(1) H. 2)lanus zoue, Cuxton. (5 — 7) A quaih-atus zone, East Haniliain. 

(2) „ „ Cheveley. (8) M. cor-anguinum zone, Willieriiii,'tou. 

(3) ,, ,, Borsteil. (9) Uintacriiius baud, Devizes Road, Salisbury. 

(4) A. quad rat U!< zone, Wbadduu railway cuttiu*,', I 





(1) 


(2) 


(3) 


(■i) 


(5) 


Length , 


. 32 


32 


26 


21 


21 


Height . 


37 


35 


30 


24 


22 



near Salisbur 



V. 



Affinities. — This species is distinguished from Linui ILqicri by having a smaller 
apical angle, by being relatively higher and shortei-, with the valves less convex, 
the anterior area relatively smaller, the entire surface of the shell always orna- 
mented, and the grooves usually deeper. 

The specimen figured by d'Orbigny as Limd Mnidelli is similar in foi'in to some 
examples of L. cretacea, but d'Orbigny states that the furrows are shallow and 
without pits. A specimen, however, in the d'Orbigny Collection at Paris shows 
pits in the grooves. 

Lima Iseviusciila, Sowerby (in Dixon) is probably a small example of this 
species, but its locality and horizon are not stated. 

One of the specimens from the Plauer-kalk of Strehlen figured by Geinitz 
(1872) as L. Hoiwrl (fig. 11) agrees very closely with this species. 

Dislrihution. — Zone of Terehratulina of Winchester. Zone of Holuder planus of 
Twyford and Cheveley. Zone of Micraster cor-testudinariunt of Borstal and 
Cuxton. Zone of M. cor-anguinum of Micheldever, Witherington and Camp Hill 
(South Wiltshire). Zone of Marsujjites of Highfield. Uintacrinus band of Devizes 
Road (Salisl)my). Zone of Arfiiiofnina.r ipuHlyiitHs of Winchester, East Harnham, 
West Harnham, and Milford (8alisl>ury). Zoue of Bclemnitella mucronata of 
Norwich. Chalk of Trimingham. 



24 CRETACEOUS LA:\1KLLIBRANCHIA. 



Tii.MA (Ti.aoiostojMa) MAiiUd'j'iANA, (VOrhiipi //, 181-7 . Plate V, figs. (!((,//, 7r',?>. 

1847. LiiMA Masrotiana, A. d'Orhigny. Pal. Frauc. Terr. Cri't., vul. iii. p. 501. 

pi. ccccxxiv, figs. 1 — 4. 
1850. — — irOrhifjny. Prodr. de Pal., vol. ii, p. 247. 

1889. — (Kadtjla) Marrotiana, 0. Griepenlierl. Seuou. vou Kouiyshiltor 

(Palseont. Abhandl., vol. iv), p. 39. 

Non 1850. - - Marottiana, A. Alth. Geogn.-pal. Beschreib. v. Lemberg (Haidinger's 

Naturwiss. Abliaudl., vol. iii. pt. 2), p. 240, 
pi. xii, fig. 25. (L. AUhi, Favre). 

Description. — Sliell of moderate convexity, oval, more or less trigonal. Antero- 
dorsal margin rather long, nearly straight ; postero-dorsal margin much shorter ; 
the remainder forming a regular curve. Umbones rather small, pointed. Apical 
angle about 105°. Anterior area large, deeply depressed, sharply limited, 
ornamented with 10 to 12 strong, rather narrow ribs, which bear, in places, small 
nodular projections. Ears rather large, with growth-ridges, without ribs ; the 
posterior rather larger than the anterior ear. 

Ornamentation consists of 30 to 32 broad ribs with a few smaller ribs near the 
posterior margin ; the ribs are smooth, with flattened or somewhat rounded 
suniiuits, and are separated by narrow rounded grooves. The grooves show, in 
places, transverse ridges and grooves which may extend to the sides of the ribs, 
giving them a notched appearance. Near the ventral margin, especially in old 
sjjccimens, the ribs become more flattened and the gi'ooves shallower. 

Measurements : 

(1) (2) 

Length . . . . 69 . 27 mm. 

Height . . . . 60 . 28 „ 

(1, 2) Upper Clialk {B. mucronata zone), Noi-wich. The measurements of the larger specimen arc 
approximate only. 

Affinities. — This is distinguished from other species found in the Chalk by its 
strong ribs. In Lima Althi, Favre, the ribs are more numerous and not so broad. 

JAnia Marrotiana differs from most of the species which are referred to 
Plarjiostoma in having much stronger ribs, but in other respects it agrees closely 
with that sub-genus. 

Remarks. — The only specimens I have seen are from Norwich, where it appears 
to be rare. The shell is usually more or less crushed, so that its proper outline is 
distditi'd. 



LIMA. 25 

T i/2)es. —WOvhigny's specimens came from the Lower Senonian of Dordogne, 
Charente-Liferieure, Cambrai, and Aube. 

Distrlhution. — Zone of Belemnitella mucronata of Norwich. 



Suh-gcnus — Acesta, II. and A. Adants, 1858. 
(' Genera of Keceut Mollusca,' vol. ii, p. 558.) 
Lima (Acesta) longa, Burner, 184L Phite V, figs. 8(i,h, 9 — 11, \2a,b. 

1836. Lima elongata, F. A. Bonier. Die Versteiu. d. nurd-deutscli. Oolith.-geb., 

p. 79, pi. xiii, fig. 11 (nou elongata, 
Sowerby). 

1841. — LONGA, Romer. Die Versteiu. d. uord-deutsch. Kreidegeb., p. 57. 

1847. — —A. d'OrhUjny. Pal. Frau9. Terr. Cret., vol. iii, p. 529, pi. 

ccccxiv, figs. 13 — 16. 

1850. — — — Prodr. de Pal., vol. ii, p. 81. 

1865. — — H. Coquand. Mou. Aptien de I'Espagne, p. 149. 

1868. — — P. de Loriol. Valaugieu d'Arzier. (Mater. Pal. Suisse, ser. 4), 

p. 41, pi. iii, fig. 11. 

1869. — —F.J. Pictet and G. Camjnche. Foss. Terr. Crct. Ste. Croix 

(Mater. Pal. Suisse, ser. 5), p. 128, 
pi. clxi, figs. 6, 7. 
1871. — — W. A. Ouster. Protozoe Helvetica, vol. ii, pp. 104, 123. ^ 

1877. — — G. Biihm. Zeitsclir. d. deutsch. geol. Gesellscli., vol. xxix, 

p. 235. 

1883. — — W. Keeping. Foss., etc., Neoc. Upware and Brickhill, p. 112, 

pi. v, fig. 6. 

1884. — n. sp., 0. Weerth. Die Fauna des Neocom. iui Teutoburg. Waldo 

(Palajout. Abliandl., vol. ii), p. 51. 
? 1895. — (Plagiostoma) cf. Eobinaldina, F. Vogel. HoUiind. Kreide, p. 56. 
1896. — LONOA, A. Wollemann. ZeitscLr. der deutscb. geol. GesellscL., 

vol. xlviii, p. 836. 
1900. — — — Die Biv. u. Gastrop. d. deutscb. u. bolliiud. 

Neocoms (Abhandl. d. k. preussiscb. geol. 
Land., N. F., pt. 31), p. 27. 

Description. — Shell compressed, sub-triangular, rounded, considerably higher 
than long, of small obliquity. Posterior and ventral margins convex; anterior 
margin straight. Umbones pointed, close together. Apical angle small — about 70°. 
Posterior ear large, not separated from the rest of the valve by a depression, 
ornamentoil with radial ribs. Anterior ear smaller, nuich higher than long. 

4 



(5) 


(6) 


21 


20 111111 


35 


32 „ 



2r> ("RKTACKOUS LA]\rKI.Ln?R.\X('ll I.\. 

Anterior area lanceolate, depressed, limited liy a sharp edge, ornamented with 
radial ribs. 

Ornamentation consists of very numerous, small, somewliat flattened ribs, 
separated by much narrower gi'ooves. The ribs are usually wavy, and are not all 
of equal size ; posteriorly smaller ribs sometimes alternate with larger. The 
grooves are punctate and vary sonieAvhat in width. A few distinct growth-lines 
are seen, below which the direction of the ribs may undergo some deflection. 

Measurements : 

(1) (2) (3) (4) 

Length . .37 35 31 23 

Height . . G2 58 5G 37 

(1, 2, 3, 5) Lower Greensand, Upware. 

(4) Tcalby Limestone, North Willinghain. 

(6) Speetou Clay, Speetou. 

Ajfinities. — Lima loiujn has a smaller apical angle and is relatively shorter than 
L. undnta, Deshayes ' ; it is also clearly distinguished by the absence of the proiiiiiit'iit 
concentric scales, and by the occurrence of pits in the grooves. 

licmarks. — In some cases, especially when the specimens are not perfectly 
preserved, the ribs (as remarked by Wollemann) become indistinct on the middle 
of the shell. This is the case in specimens from the Tealby Limestone, and in some 
from the Speeton Clay, in which the iniddle ])art of the shell is almost smooth. 
The outline of the shell and the I'elative size of the posterior ear are rather variable. 

A specimen from West Dereham (Plate V, fig. 13) possesses finer ribs, but may 
perhaps be only a variety of this species. 

Tjipes. — From the Ililsthon of EUigser Brink. A specimen from the same 
locality (imperfect on the posterior side of the umbo) is figured by d'Orliigny and 
is preserved in the Museum of Palaeontology at Paris. Two oF the sj^'cimeiis from 
Upware figured by Keepuig are in the Sedgwick Museum, Cambridge, and auotiier 
is in the collection of Mr. J. F. Walker. 

JJistribulioii.—hovfev Greensand of Upware, Potton, and Priekhill. Tealby 
Limestone (zone of JJdemnites brans oicensis) of North Williughani. Ujiper part of 
Speeton Series of Speeton. 



TiiMA (Acksta) CLYPElFOKMis, (VOrJihjii ij, 1817. Text-figure 5. 

1847. Lima clypehokmis, A. d'Orhiijiitj. Pal, Fraiu;. Terr. Crt't., vol. iii, p. 543, 

pi. ecccxvii, figs. 9, 10. 
1860. — — d'Orbigny. Prodr. de Pal., vol. ii, p. 166. 

^ See d'Orbiguy, p. 528, pi. ccccxiv, figs. 9 — 12 ; Pictet aiid Campiche, p. 133, pi. clxii, fig. 1. 



LIMA. 



27 



I860. Lima cltpeiformis, F. J. PU-ld ami G. Campirhf. Foss. Terr. Crt't. Sto. 

Croix (Mater. Pal. Suisse scr. 5), 
p. 168. 
1871. Radui.a (Acesta) cltpeiformis, F. Stolkzlca. PaliBont. Imlica, Cret. 

Fauna S. India, vol. iii, 
p. 414. 



Description. — Shell very large, compressed, oval, rounded, only slightly oblique. 
Height equal to or slightly greater than length. Antero-dorsal margin more or less 




Fio. 5. — Lima {Acesta) elypeiformis, d'Orbi^ny. Upper Greensnud, Chard. Eight valve. Taunton 

Museum, x |. 

straightened and relatively short. Ears rather small, the anterior larger than the 
posterior. Siu-face of shell smooth, except for growth-lamella) at intervals. 
Measurements : 

Length 100 mm. 



Heiglit 



. 1()S „ 



Upper Greensand, CLard. 



28 CRETACEOUS LAMELLTRRANCHTA. 

Affimiies. — Lima siihch/jmformis, Fiitterer,^ is stated to be related to //. rh/jm- 
formis. 

Rcmarls. — This is the largest species of JAina known in the Cretaceous of 
England. I have seen two specimens only, one of which is in the Museum of the 
Somersetshire Archreological and Natural History Society at Taunton, and the 
other in the Exeter Museum. The occurrence of this species in England was tirst 
recorded by Mr. Jukes-Browne." 

Type. — D'Orbigny's specimens came from the Ccnomanian of Le Mans, etc. 

DistrilmHoii. — Topmost bed of the Upper Greensand of Chard. 



Suh-genus — Mantellum, J. F. Bolfen, 1798. 
('Mus. Bolten.; 2. p. 100.) 
Lima (Mantellum) parallela (Soiverhy) 1812. Plate V, figs. M-, '[ba—ih 

1812. MoDiOLA PAEALLELA, J. ih C. Soiverhy. Miu. Condi., vol. i, p. 31, pi. ix 

(right-haud top figure). 
1842. Lima elegans, A. Leijmeric Mi'm. Soc. gi'ol. de France, vol. v, ]>. 27, 

pi. vi, fig. 6. {Non Dujardiu, non Nilsson. ) 

1845. — elonoata, E. Forbes. Quart. Jouru. Geol. Soc, vol. i, p. 248. 

1846. — ELEGANS, A. Leymerie. Statist, geol. et min. de rAubc, pi. vi, fig. 7. 

1847. — CoTTALDiNA, A. (TOrhigmj. Pal. Fran9. Terr. Crct., vol. iii, p. .''>37, 

pi. ccccxvi, figs. 1 — 5. 
18,50. — — d'Orhigny. Prodr. de Pal, vol. ii, p. 119. 

1854. — PARALLELA, /. Morris. Cat. Brit. Foss., ed. 2, p. 171. 

1855. — CoTTALDiNA, G. Gotteau. Moll. Foss. de I'Yonne, p. 101. 

1858. — — J. Vilanova-y-Piera. Mem. geog.-agric. de Castellon, 

pi. ii, fig. 15. 
— — PAEALLELA, F. J. Pictet and E. Benevier. Foss. Terr. Aptiou (Mator. 

Pal. Suisse, ser.l), p. 126, 
pi. xix, fig. 1. 
18C5. — — H. Coquand. Men. Aptien de I'Espagne, p. 148. 

1869. — COTTALDINA, F. J. Pictct uiul G. Campicke. Foss. Terr. Cret. St«. 

Croix (Mater. Pal. Suisse, ser. 5), 
p. 151, pi. elxvi, fig. 1. 

1883. — rARRiNQDONENSis, W. Keejuug. Foss., etc., Neoc. Upware and Brick- 

hill, p. 112, pi. V, fig. 12. 

1884. — COTTALDINA, O. WpcrtJi. Die Fauna des Neocom. im Teutoburg. 

Walde (Palaeont. Abhandl., vol. ii), p. 52. 

' ' Kreidebild. d. Santa Croce in den Venctianer Alpen ' (Pala;ont. Abhandl., vol. vi, 1892), 
p. 78, fig. 23. 

2 ' Proc. Somerset ArchEool. and Nat. Hist. Soc.,' vol. xlix, 1903. 



LIMA. 2y 

1895. Lima Cottaldina, G. Maas. Zeitschr. <ler deutscli. gcol. Gesellsch., vo . 

xlvii, p. 267. 
— — (Rabttla) Cottaldina, F. Vognl. HollaiKliscli. Kreide., p. 56. 

1900. — Cottaldina, A. WoJIrmnnn. Die Biv. u. (iastrop. d. deutsch. n. 

liolliind. Neocoms (Abliandl. d. k. 
preussisch. geol. Land., N. F., pt. 
31), p. 35, pi. ii, figs. 2, 3. 

Non 1847. — parallela, (VOrhupiy. (See p. 31). 

Description. — Shell modei'ately convex, oblique, oval or rounded-ojjlong, higher 
than long. Antero-dorsal margin long, nearly straight, more or less parallel with the 
postero- ventral margin ; postero-dorsal margin short, more or less nearly straight. 
Anterior margin regularly rounded. Umbones sharp, only slightly curved ; apical 
angle about 90°. Ears of moderate size. Anterior area rather large, slightly 
convex ventrally, depressed near the umbo, usually smooth except for growth- 
lines. 

Ornamentation consists of 18 to 20 principal ribs, and sometimes of a few- 
smaller ribs near the posterior margin. The principal ribs are roof-like with sharp 
summits ; they are strongest on the antero-dorsal part of the valve and ])econie 
less elevated and rather more widely separated in passing posteriorly ; the two or 
three anterior ribs (near the anterior area) are rather smaller and closer together. 
A small rib occurs at the bottom of the furrows between the main ribs ; smaller 
linear rilis may occur on the sides of the principal ribs, especially on the posterior 
part of the shell. Fine concentric growth-lines are seen on the ribs and furrows. 

Measurements : 

(1) (2) (3) (4) (.-i) 

Length . 2G 26 25 23 23 
Height . 21 22 20 19 18 

(1, 4) Perna-hcd, Atherfield. 
(2, 5) Hythe Beds, Lympue. 

(3) Lower Greensand, Upware. 
{G, 7) Hythe Beds, Hythe. 

(8) Ferruginous Sands, Shanklin. 

Affinities. — This species is closely allied to L. Enijennna, d'Orbigny," but in 
the latter the ribs do not decrease in size nor become more widely separated on 
the posterior part of the shell, and the suuill rib in the furrows is absent or 
indistinct. 

L. parallela. is distinguished from L. gaultina (p. 31) l)y l)eing relatively 
shorter and less compressed, by the ribs on the posterior part of the shell being 

' 'Pal. Fran9. Terr. Cn't.,' vol. iii (1847), p. 527, pi. ccccxiv, figs. 5 — 8; Pictet and Campiche, 
'Terr. Cret. Ste. Croix ' (1869), p. 142, pi. clxiv. figs. 4, 5. 



(6) 


(-) 


(S) 


22 


19 


14 mm 


17 


k; 


11 „ 



30 CRETACEOUS LAMELTJBEANCHIA. 

more distinctly siiialk'r tluiii those on tlio anterior pnrt, nnd l)y tlie presence of 
tlie small rib at the l)ottom of each groove. Sec also L. J'lii-i-iiiiiilniiri/sis (below). 

L. exjmnsa, Foi-bes,' fi-oni the ITythc Beds of Hythc, is known to me only from 
the type specimen which is preserved in the Musenm of the Geological Society 
(No. 2050). It is an internal cast in clay, somewhat crnshed, and shows the 
ribbing only imperfectly. I think it is i)robal)ly an example of L. paralJcht, bnt 
more specimens from the same horizon are needed Ijefore a confident opinion can 
be given. Similar remarks apply to L. lingua, Forbes," which comes from the same 
horizon and locality, and is likewise preserved in the Museum of the Greological 
Society (No. 2058). 

This and the following eight species are provisionally referred to the sub-genus 
Md 11 1 I'll urn, with which they agree in the form of the shell and, in many cases, in 
the general character of the ornamentation. They differ, however, from the type 
of Maidelliim in having the valves closed or almost closed, but there is, as Phillipi 
has pointed out, every transition from the species in wliicli tlio \;ilves gape \vi<lcly 
to others in which they are closed. 

I'riinirJrx. — This species shows a fair amount of variation in the ]iro]iortions of 
length and height, and also in the obliquity of the shell. 

The type-specimen of L. 2^'i>'M''l'^ is an internal cast, and consequently all 
writei's liave found it practically impossible to make out the charact(>i's of the 
species from Sowerby's figure. A comparison of the type with better preserved 
specimens leaves no doubt in my mind that Sowerl)y's species is really identical 
with the form described by d'Orbigny as L. ('(itlnJiVuni. The latter author 
I'cfei'red a species found in the Gault (/y. ijditHiiKi, p. ol) to L. pandlcla, Sowerby. 

'I'l/ji'-x. — The type is from the Ilythe Beds of Maidstone and is preserved in the 
Hi'itish Museum (No. 4o,2i)2). The specimen from Upware figured as L. faniiiij- 
(Idiit'iisis by Keeping is in the Sedgwick Museum, Cambridge. 

Dixfrihiitiou. — Prrna-hed and Atherfield Clay of Atherfield. Ferruginous Sands 
of Shanklin. Hythc licds of Hythc, T.ympne, and Maidstone. Sandgate Beds of 
Sevenoaks. Folkestone Beds of Folkestone, [jower Greensand of Faringdon and 
Upware. Speeton Clay of Speeton. 



Lima (Mantktjjim) farringdonensis, Sharpr, 1853. 

1853. Lima farringdonensis, D. Sharpe. Quart. Jdiini. Gcol. Soc, vol. \, p. 198, 

pi. vi, fig. 2. 

Non 1883. — « — W. Keeping. Fuss., etc., Neoe. TJpware and ■Brick- 

hill, p. 112, pi. V, tig. 12. 

' 'Quart. JouiTi. Geol. Soe.,' vol. i (1845), p. 249, pi. iii, fig. 11. 
- Ibi.L, p. 249, pi. iii, fig. 10. 



LIMA. 31 

Renin fliS. — The cliiof cliavucter in which Liittit Juningtloiiru.sis differs from 
L. parallela seems to be in the possession of well-marked ribs over the whole of 
the anterior area. It also differs from the majority of examples of L. parallda in 
that the ribs only decrease in size to a very small extent in passing from the 
anterior to the posterior part of the shell; and further, the shell is less inequilateral 
than is usual in L. parallela. 

I am inclined to regard Lima farrliigdonensis as not more than a variety of 
L. paraUcla, but without better material it is impossible to express a confident 
opinion. Almost all the specimens seen are in the condition of intei-nal casts in a 
brownish ferruginous sandstone. 

Type. — The figure given by Sharpe is taken from a gutta-percha cast of an 
external mould. It was obtained from Seende and is preserved in the Museum of 
the Geological Society. 

Bidribution. — Lower Grcensand of Seende and Faringdon. 



Lima (M.vntelt.um) uaultina, nom. nov. Plate V, figs. IG — 2(>. 

? 1827. Plagiobtoma elongata, /. Jc C Smvcrhij. Miu. Couch., vol. vi, ji. 113, 

1)1. dlix, fig. 2 (upper figure ouly). 
1847. Lima paeallela, A. d'Orhitjuy. Pal. Frauc. Terr. Crt't., vol. iii. p. 539, 

pi. ccccxvi, figs. 11 — 14. 
1850. — — d'Orhlijiiij. Prodi-, de Pal, vol. ii, p. 138. 

1855. — — G. ColteiiH. Moll. Foss. de ITouue, p. 101. 

1854. — elongata, /. Murris. Cat. Brit. Foss., ed. 2, p. 171 (jjaiiim). 
1875. — — A. J. Jukes-Browne. Quart. Jouru. Geol. Soc., vol. xxxi, 

p. 2;i(i. 
1897. — parallela, R. B. Ncwtun. Proc. Dorset Nat. Hist, aud Autiij. Field 

Club, vol. xvii, p. 88, pi. iii, fig. 11. 
IPOO. — — E. T. Newton aud .1. J. Jukes-Browne. Cret. Eocks of 

Britain, vol. i, p. 449. 

Nou 1850. Plagiostuma parallelus. J. de C. Suwerbij iu F. Duoii. Geol. Sussex, 

p. 35t) (p. 386, ed. 2), pi. xxviii, 
fig. 16 (=1/. elongata, Sowerby). 

Description. — Shell rather compressed, sulj-cpiadrangidar or nearly oblong, very 
oblique, nuich longer than high, rounded posteriorly ; antero-dorsal margin long 
and nearly straight, almost parallel with the postero-ventral margin. Apical angle 
about 100°. Umbones pointed, close together. Ears of moderate size, the anterior 
larger than the posterior. Anterior area lai-ge, slightly concave dorsally, orna- 
mented with fine radial ribs. 

Ornamentation consists of 18 to '20 main rilis witli a few smaller ribs pos- 
teriorly. The ribs are strong, witli sharp summits, but become somewhat 



32 CRETACEOUS LAMET/IJBRANCHIA. 

weaker posteriorly. The sides of the ribs are oriianiented witli fine radial ribs, and 
at the summit there is sometimes a rib with pointed projections. Concentric 
growth-lines are present. 
Measurements : 

Length 
Height ' . 



(1) (2) (3) (4) 


(5) 


(6) 


39 3-1 29 29 


28 


17 mm 


28 23 20 18 


20 


I'' 


(1, 4) Gault, Black Veu. 






(2, 3, 5, 6) Gault, Folkestone. 







Affinities. — Lima Itcviana, Pictet and Roux,- appears to differ from this species 
in having a small rib at the bottom of the groove, and in being relatively shorter. 
Pictet and Canii)iche state that the small rib is not always present. I have seen 
no trace of such a rib in even the best preserved examples of L. gunltina. See also 
Lima elomjata (p. 36). 

Bemarls. — One of the specimens figured by Sowerby as Flagiostoma cloinjutu 
(the upper figure 2 of Plate DLIX) is probably an exanii)le of this species, but since 
it is an internal cast only, it is difficult to be sure of its identity without seeing 
other specimens from the same horizon. The specimen in question, however, 
asfrees in form and in the characters of the ribs with other internal casts which 
imdoubtedly belong to this species. D'Orbigny referred this species to Lima 
■paraUcla (Sowerby) and also included with it L. cloiujata, Sowerby (p. 3-1). 

Types. — The specimen figured by Sowerby, mentioned above, is stated to come 
from the " Greensand of Folkestone." D'Orbigny's specimens of LAma paralhla, 
d'Orbigny non Sowerby, came from the Gault of Gerodot and Dienville (Aube). 

Distribution. — Gault of Folkestone (zones ii, vii, ix). Gault of Veutnor and 
JJlack Ven. Cambridge Greensand (derived). Upper Greensand (zone of 
ScldcJOidHichia roslrata) of Devizes. Internal casts from the Speeton Clay (zone of 
Belemnitcs jacidum, C 11) seem to be indistinguishable from this species. 



Lima (]V1anteija:m) inteulinkata, Jukes- Bruwtw, 1877. Plate VI, figs, ia, I/. 

1877. Lima interlinbata, A. J. Jukes-Browne. Quart. Journ. Geol. Soc, 

vol. xxxiii, p. 502, pi. xxi, fig. 10. 

Dfxrrqilii)n. — Shell moderately convex, roundetl-ublong. Umbones and ears 
uuL seen. 

' Measured perpeinlicular to the liiugc-line. 

2 'Moll. Foss. Grts verts ile Geuive " (1852), p. 484, pi. xl, fig. 5 ; F. J. Pietet aud G. Caiupiehe, 
'Foss. Terr. Crct. Sto. Croix ' (Mater. Pal. Suisse, ser. 5, 1869), p. 156, pi. clxvi, figs. 4, 5. 



LIMA. 33 

Ornamentation consists of 10 to 12 sti'ong ribs witli l)road interspaces. On the 
posterior part of the shell the ribs are more widely separated and the interspaces 
flatter than on the anterior part. In the interspaces there are small i^adial ribs 
separated by broad spaces. 

Bemarlcs. — The only specimens seen are a few imperfect internal moulds with 
very small portions of the shell preserved. L. iiderlincata a^ipears to l)e allied to 
L. gaultlua (see above) but is distinguished by possessing fewer ribs with broader 
and flatter interspaces. The smaller radial ribs are perhaps also better developed 
than in L. gaultlua. 

Tijpe. — In the Sedgwick Museum, Cambridge. 

Didrihuiion. — Cambridge Greensand (derived from the Gaidt). 



Lima (Maxtelluji) iNXEUMEiUA, iVOrJihjinj, 1847. Plate VI, figs. 2 «, ?^, 3, 4a — c. 

1847. Lima inteemeuia, A. d'Oi-hijnij. Pal. Fiau9. Terr. Cret., vol. iii, p. 550, 

pi. ccccxxi, figs. 1 — 5. 
1850. — — d'OMijiiij. Prodr. de Pal., vol. ii, p. 167. 

1869. — — F. J. Pldd and G. Campkhc. Foss. Terr. Cret. Ste. 

Croix (Matur. Pal. Suisse, ser. 5), 
p. 168. 
? 1877. — — A. Fritsch. Stud, im Gebietc derbiilim. Kreideformat. : 

II, Weisseuberg. u. Maluitz. Scluclit., 
p. 134, fig. 123. 

Descriptlou. — Shell moderately compressed, oblique, oval or rounded-ol:)long, 
higher than long. Antero-dorsal border rather long and roughly parallel to tlie 
slightly curving postero-ventral border; both curve gradually and regularly to 
join the posterior border. Postero-dorsal shorter than the antero-dorsal border. 
Umbones inconspicuous, close together. Apical angle about 100°. Ears small, of 
nearly equal size, the posterior with three or four small radial ribs and with growth- 
ridges. Anterior area moderately large, slightly convex except near the umbones, 
smooth or with a few small ribs at the sides. 

Ornamentation consists of 20 to 23 ribs. Those on llie antero-ventral region 

are strong and roof-like, and, in old specimens, bear a smaller rilj on each 

side; posterior to this region the ribs become much smaller and less elevated, 

some being almost linear and Avith broad and nearly flat interspaces. At the 

bottom of the furrows and in the middle of the flat interspaces there is a linear 

rib. In well-preserved specimens very fine radial ribs and concentric lines 

are seen. 

5 



34 CRETACEOUS LAMELLIBRANCHIA. 



Measurements : 










(1) 


(a) 


(3) 


Length 


35 


30 


30 nun. 


Height 


31 


28 


2G „ 


Thickness 


18 


17 


16 „ 



(1,2) Kye Hill Sands, Warminsler. 

(3) Upper Greensand, Longbridge, Devizes. 

Affinities. — This species is closely allied to Liina parallela, Init is distinguished 
by being less convex (especially in the region of the umbones), Ijy Ijoing rather 
shorter and higher, and by the ribs decreasing in size rather more rapidly when 
traced from the antero-ventral region to the posterior region. The fine radial orna- 
mentation is also perhaps rather better marked than in L. parallela. 

L. intermedia differs from L. elongata (see below) in being less convex, relatively 
shorter, in the ribs being less elevated and decreasing in size posteriorly, and in the 
absence or indistinct character of the ribs on the anterior area. 

It is also relatively shorter and higher than Lima gaultina, and the ribs on the 
posterior half are much smaller and have broader and flatter interspaces. The 
intermediate rib is distinct in L. intermedia, but is absent or indistinct in L. ydtdtina. 

Type. — From the Cenomanian of Le Mans. 

Distrihiitlon. — Upper Greensand (zone of Pecteii asper) of Longbridge, near 
Devizes. Rye Hill Sands of Warminster. 



Lima (Mantellum) elongata (Sowerbij), 1827. Plate VI, figs. 5, 6a— c, 7a, b. 

1822. Plagiostoma, G. Mantell. Foss. S. Downs, p. 129, pi. xix, fig. 1. 
1827. — ELONGATA, /. (le C. Sowcrhij. Min. Couch., vol. vi, p. 113, 

pi. dlix, fig. 2 (lower tigiu-e). 
? 1847. Lima Astieeiana, A. d'Orbiijny. Pal. Frdiu;. Terr. Cret., vol. iii, p. 549, 

pi. ccccxx, figs. 4 — 7. 
1850. Plagiostoma paeallelus, /. de C. Sowcrhy in F. Dixon. Geol. Sussex, 

p. 350 (p. 386, ed. 2), pi. xxviii, fig. 16. 
1854. Lima elongata, /. Morris. Cat. Brit. Foss., ed. 2, p. 171 (jMrtim). 

1869. — — F. J. Fidct and G. Cttm]jiche. Foss. Terr. Cret. Ste. Croix 

(Mater. Pal. Suisse, ser. 5), p. 168. 

1870. — — F. R'dmer. Geol. vou Oberscliles., p. 343, pi. xxix, fig. 1. 
? 1876. — — H. Deicke. Toui-tia vou Miillieim a. d. liuhr, p. 27. 

'^ 1877. — — G. Bijhm. Zeitsclir. d. deutsch. geol. Gesellscli., vol. xxix 

p. 234. 
1897. — — R. Leonhard. Kreideformat. iu Oberscliles. (Palajonto- 

grapliica, vol. xliv), p. 47. 
1904. — — E. T. Newton and A. J. Jukes-Browne. Cret. Kocks of 

Britain, vol. iii, p. 451. 



LIMA. 35 

Noil 188G. Lima elonoata, A. Gohlfiufs. Petref. Germ., vol. ii, p. 87, pi. cii, fi;,'. 13 

{L. Miinsteriana, (l'Orl)igny). 
— — — F. A. lli'imcr. Vcr.stoiii. nord-deutscli. Oolith.-geb., p. 70, 

111. xiii, fig. 11 {L. lontjn, Komor, 1841). 
? — 1841. — — F. A. Biimer. Die Verstein. d. iiord-dcutscli. Kreidegeb., 

p. 5G. 

— 1845. — — H. Forhes. Quart. Joum. Geol. Soc, vol. i, p. 248 (L. 

parallela, Sowerby). 
? — 1846. — — A.E.Reuss. Die Verstein. der bijlim. Kreideformat., pt. 2, 

p. 33, pi. xxxviii, fig. 6, non 9 (= i. Reiigm, 
d'Orb.). 

— 1863. — — A. V. Stromhech. Zeiisclir. d. deutsch. geol. Gesellsch., 

vol. XV, p. 104 {L. Schmeisseri, 
Wollemauu). 
? — 1872. — — H. B. Geinitz. Das Elbtlialgeb. in Sachscn (Palffiouto- 

graphica, vol. xx, pt. 2), p. 40, pi. ix, 
figs. 9, 10. 
'■ — 1877. — — A. Fritscli. Stud, im Gebiete der bolim. Kreideformat.: 

II, Weisseuberg. u. Malnitz. Scbicht., p. 132, 
fig. 116. 

Description. — Shell of moderate convexity, subquadrangular or nearly olilonp-, 
rounded anteriorly, mucli longer than high. Antero-dorsal margin long, nearly 
straight, and nearly parallel with the postero-ventral margin; postero-dorsal 
margin short, nearly straight. Apical angle about 100°. Umbones sharp, close 
together. Ears of moderate size. Anterior area large, the dorsal part slightly 
concave, ornamented with from five to seven fairly strong riljs which are crossed 
by fine growth-ridges. 

Ornamentation consists of 19 or 20 very strong ribs, with sharp, and some- 
times (especially on the dorsal part of the shell) slightly serrate summits. The 
ribs have usually at their summits a distinct ridge with a shallow fiu-row on each 
side, which sometimes gives rise to the appearance of a ridge on each side of the 
rib. The grooves between the main ribs are deep, rounded, distinctly limited, and 
of a])out the same width as the ribs. On the~dorsal portions of the shell fine radial 
ribs occur on both ribs and grooves ; on the ventral portions they are not seen. 
Fine concentric growth-lines cross both ribs and grooves, and some few (at 
intervals) are more distinct. 

Measurements : 

Length 
Height 

(1. 3, 5, 6) Chalk Marl, Folkestone. 

(2) H. suhyhthomg zone, Stoke Ferry. 
(4) Chalk Marl, Veutnor. 



(1) 


(2) 


(3) 


(4) 


(5) 


(6) 


34 


27 


26 


25 


24 


24 mm 


24 


18 


20 


20 


18 


17 „ 



36 CRETACEOUS LAMELLIBRANCHIA. 

Affinities^. — This species agrees in form witli Lima gauUiva (p. 31), but is 
distinguished (1) by the stronger ribs on tlic anterior area, (2) by the grooves being 
relatively broader and more distinctly limited, (3) l)y the ribs being more elevated, 
(4) by the fine radial ribs being usually indistinct except on the dorsal portions of 
the shell. 

The form from the Pliiner-kalk (Turonian) of Saxonj' figured as JAma 
elongata by Geinitz seems to differ from this species in having fewer and more 
rounded ribs, and in the ribs being more Avidely separated on the posterior part of 
the shell than elsewhere. Similar remarks apply to the specimen figured by 
Fritsch. Without the opportunity of comparing specimens I am unable to give a 
definite opinion as to the Turonian form being distinct from L. chmfintd. 

Lima AMerianii, d'Orbigny, is perhaps identical with Z. elongata, but the summits 
of the ribs appear to be somewhat more rounded. 

Lima Beussi, d'Orbigny {L. ehngata of Reuss) seems to differ from Lj. elongata 
in having a smaller apical angle. 

BemarJcs. — Under the name FJagiostoma ehngata Sowerby figured two species. 
It seems advisable to retain the name elongata for the one shown in the lower of his 
two figures, since that form had liecn previously figured and described (but without 
a specific name) by Mantell, and Sowerby refers to Mantcll's figure as an example 
of Plagiostoma elongata. 

T)jpe>i. — I have not seen the specimen figured by Mantell. Sowerby's type, 
from the Chalk Marl of Hamsey, and also the specimen figured in Dixon's work are 
in the British Museum. 

Distribution. — The range is from the Chloritic Marl to the zone of TTolaster snli- 
glohof^ns. Chloritic IVIarl of Eastbourne and the Isle of Wight. Chalk Marl of 
Ventnor, Folkestone, and Prince's Risborough. Totternhoe Stone of Arlesey. 
Zone of IIola><t('r siihijliit)(i><n>< of l^luo Bell Hill (Bnrhani), Stoke Ferry, and 
Hunstanton. 



Lima (Maxtelta-m) klonciata, var. echinata, Ethf ridge, 1881. Plate VI, figs. 8, 9 a — c. 

1881. Lima eohinata, R. Etheridgr. lu Penniiuj and Jukes-Browne, Geol. Cam- 
bridge, p. 144, pi. ii, fig. 2. 

Remarks. — The examples described by Etheridge as Lima echinata agree 
perfectly in form, in size, and in the number and character of the ribs with Tj. 
elongata, but on the ridge at the summit of each rib there is a roAV of short spines 
which are frequently rounded and stumpy, and on each side of the rib (outside the 



LIMA. 37 

slmlloAV groove nuMitioiied in tlic description of Tj. plonfjafd) tliore is another row of 
similar, but slightly smaller spines. In the furrows between the main ribs there 
are transverse ridges. 

On account of the close resemblance in the form and ribbing of //. orhinaid 
to L. olongntn, and also from the fact that \n some specimens of the former the 
ornamentation of the ribs is absent from a part of the shell and the ribs are tlion 
indistinguishable from those of L. cloiigatu, I am led to consider L. rchinata as not 
more than a variety of L. elongafa. Further, in some specimens of L. doiigata the 
summits of the ribs are serrate. 

L.rlonr/nta var. echinata pi^esents some resemblance to L.Schmeiswri, Wollemann,' 
from the BJiotomagensis-'Pliinev of Liineburg. 

Ti/pes. — In the Sedgwick Museum, from Burwell. 

Diiifrihiifinu. — Totternhoe Stone {Tfdhi.^fi'v siihglohnftus zone) of Burwell and 
Cherry Hinton. Also recorded in the ' Geological Survey Memoirs ' from the zone 
of Schhriiliiichia cariaiis. 



Lima (Mantellum) rAXTATiRKUEXSis, nom. nov. Plate VI, figs. 10a, h, 11, 12. 

1881. Lima ornata. 7?. Ether'nhje. In Pcnnimj and Jukes-Browne, Geol. Cam- 
bridge, p. 144, pi. iii, fig. 2 (lion 
ornata, d'Orbigny, 1847 ; nr>ii 
ornata, Buvignicr, 1852). 

Dpscriptinn. — Shell moderately convex, oval or rounded-oblong. Anterior 
margin rounded. Uml)ones and ears not seen. 

Ornamentation consists of 16 or 17 main ribs with a few small ribs at the 
posterior end. The anterior ril)s are sti'ong, roof-like, with ridged summits ; 
posteriorly the ribs become less prominent and the interspaces less depressed. 
Both ribs and grooves are ornamented with fine, well-developed ribs, which arc 
closer together on the ribs than in the grooves ; usually three or four occur on 
each side of a main rib and three in each erroove. iSTumerous concentric rids:es 
occur and give rise to spiny projections where they cross the fine radial ribs. 

Affinitipn. — In form this appears to be similar to L. pamllehi (p. 28), but has 
fewer ribs and is much more highly ornamented. The small rib at the bottom of 
the groove is not distinguishable from the other ribs. 

It is more convex, has fewer ribs, and has the fine ornamentation better developed 
than in L. intermedia. 

Iii-Diarh. — This species is known b}' three specimens only. All arc imperfect 
near the umbo, but the fine ornamentation is well-preserved. 

' Abhandl. d. k. proussiscli. geol. Landesanst., N. F.,' Heft 37 (1902), p. 5.1, pi. vii, fig. 9. 



38 CRETACEOUS LAMELLIBRANCHIA. 

Oil account of the name ornata having been previously used by d'Orbigny and 
by Buvignicr for other species it is necessary to substitute some other name. 

Ti/pf's. — From the Cambridge Greensand (indigenous), preserved in the Sedgwick 
iMnsoum, Cambridge. 

liislriJiiifloK — Cauibridge (ircensaud (iii(bgoiinus). Lower Chalk of Burwcll. 



Til MA (Mantellum) liiMTAXxicA, sp. uov. Plate VI, figs. 13^^ — (L 

18-j7. Lima elegans, J. W. SaUer. Quart. Jouru. Geol. Soc, vol. xiii, p. 8.5, pi. ii, 

fig. 3 (non eJegans, Nilssou). 

Dc^criiiiion. — Shell moderately conA'ex, sub-quadrate or nearly oblong, very 
oblique. Antero -dorsal and postero-ventral margins more or less parallel ; pos- 
terior margin rounded. Ears of moderate size, with a few ribs on the inner 
portions, and with distinct growth-lines; the anterior larger than the posterior 
car. Anterior area not distinctly limited, covered with ribs similai- to those on the 
rest of the valve but of nearly uniform size. 

Ornamentation consists of eighteen main ribs, which are strong on the anterior 
part of the shell, but become smaller in passing to the posterior end. At the 
summit of each main rib is a narrow, elevated, secondary rib, and on each side of 
a main ril) are two or three similar Init rather small ribs. The secondary rilis are 
separated by broad and rounded furrows. The summits of the secondary ribs 
are usually sharp and even, but occasionally slightly serrate. 

Measuremeutfi: 

Length 19 mm. 

Height 24 „ 

Afflvitirf^. — This form, of which I have seen one example only, agrees with the 
specimen preserved in flint from Moreseat (Aberdeenshire) which was described 
and figured by Salter as Ijhna clrgans (Xilsson). That specimen is now in the 
Museum of Practical Geology. Nilsson's' figure is scarcely sufficient to enable one 
to determine the species, Init from the recent illustrations given by Hennig- it is 
seen that the British specimens differ from Lima elegans in being more distinctly 
oblong and especially in having more numerous secondary ribs. 

1 'Petrif. Suecana' (1827), p. 20, pi. ix, fig. 7; Hisiuger, ' Lethsea Suecica ' (1837), p. 55, pi. xv, 

fig. 10. 

2 Eovis. Lamelllbr. i Nilsson's ' Petrif. Suecaua' (1897), p. 33, pi. ii, figs. 9, 10, 11. 2t; Lima 
elegans, Dujardin ('Mem. Soc. geol. de France,' vol. ii, 1837, p. 226, pi. xvi, fig. 1), is apparently 
distinct from Nilsson's species. 



LIMA. 3<J 

Type. — In the collection of ]\Ir. R. M. Brjdone. 

Distribution. — Lower part of the zone of Mifnintfr (■iii--an(jaiuniii of Suaford. 



LiiiA (Mantellum) Rkicuexuacui, CIcinit::, 1839. i'luLe VI, figs. 1 !■(/, A, 1-J. 

1839. Lima Eeichenbachi, II. B. GeiiiUz. Char. d. Schiclit. ii. Petref. des sik-hs. 

Kreidegeb., pt. 1, p. 24, pi. viii, 
fig. 4. 
1841. — Eeichenbachii, i^. ^i. ijiimec. Die Versteiu. d. uord-deutsch. Kreide- 

geb., p. 57. 
1843. — Eeichenbachi, H. B. Gcinih. Die Versteiu. vuu Kieslingswalda, 

p. 23, pi. V, fig. 9. 
184(3. — — A. E. Eeuss. Die Versteiu. der boliiu. Kreideforuiat., 

pt. 2, p. 34. 
1847. — Eeichenbachii, A. d'Orhujmj. Pal. Frau9. Terr. Crc't., vul. iii, p. 544, 

pi. ccccxviii, figs. 1 — 4. 
1860. — Eeichenbachi, H. B. Geinitz. Das Quadersaudst. oder Kreidegeb. 

ill Deutschlaud, p. 190. 
— — Eeichenbachii, A. d'Ofhiyny. Prodr. de Pal., vol. ii, p. 166. 

1855. — — G. Cotteau. Moll. Foss. de I'Youue, p. 101. 

1867. — — E. Giuramjer. Album Palcont. de la Sartlie, p. 19, 

pi. xxiv, fig. 5. 
1869. — Eeichenbachii, F. J. Pictet and G. Camjnche. Foss. Terr. Crt't. Ste. 

Croix (Matur. Pal. Suisse, 
ser. 5), p. 168. 
1872. — — H. B. Geinitz. Das Elbthalgeb. iu SacLseu (Pal- 

seontographica, vol. xx, pt. 1)^ 
p. 203, pi. xliii, figs. 1, 2. 
1876. — Eeichenbachi, H. Deiclce. Tourtia v. Miillieiui a. d. Eulir, p. 27. 
1882. — Eeichenbachii, P. de Loriol. Gault de Cosue, p. 101, pi. xiii. fig. 5. 

Description. — Shell convex, oblong, oblique, rounded ventrally; autero-dorsal 
margin long, nearly straight and almost parallel with the opposite margin. Height 
considerably greater than length. Anterior area large, smooth, not depressed. 
Ears rather small, the anterior somewhat larger than the posterior. 

Shell ornamented with from seven to ten very strong ribs, which have romided 
summits and are separated by rounded grooves of about the same width as the 
ribs. Small and narrow radial ribs are present on both ribs and grooves. 

Measurements : 

(1) (2) (3) 

Length . 29 . 25 . 21 ram. 

Height . 35 . 3-A . 27 „ 

Thickness . 19 . U) . — „ 

(1 — 3) Oenouianiau, Wiliningtou. 



40 CRETACEOUS LAMELLIBRAXCHIA. 

liciiKirks. — This species is easily distiuguislied b_y the very strong radial ribs. 
The English sjiecimens, which at present are known from three localities only, are 
not well-preserved, so that the details of the ornamentation cannot be seen clearly. 

The occm'rence of L. lieichenbacld in England (from Wilmington) was first 
noted by Mr. Jukes-Browne in 1898. The only specimens which I have seen are 
now in the Museum of Practical Geology and the Sedgwick Museum. 

Types. — From the Lower Planer (Cenomanian) of Plauen near Dresden. 

Distrihutioh. — Upper Greensand (zone of Peden aspcv) of Warminster. 
Chloritic Marl of Chard. Cenomanian Sandstone of Wilmington. 



Lima (]\L\ntellum), sp. Plate VI, fig. IG a, h. 

BeiiLdiii-". — A small specimen in the Museum of Practical Geology (Xo. 7896) 
is similar in form and in the general character of its ornamentation to L. canta- 
hr'ujiensiti (see p. 37), but the main ribs are not so strongly developed, the 
interspaces are flatter, and the intermediate ribs are more prominent. It differs 
from L. intermedia in its more distinctly oblong form and in the occurrence of 
well-developed intermediate ribs. 

This specimen resembles closely the lowest of the three figures referred io Lima 
elegans by Gucranger.^ 

Distribution. — Chloritic Marl of Chardstock. 



Sab-genus — Ctenoides, II. (ind A. Adams, 1858 (ex Klein, 1753). 

('Genera of Keceut Mollubca,' vol. ii, p. 557). 

LiM.\ (('TE\(m.|.>) \\\v\, d'Orbiijinj, 1847. Plate VI, figs. Ma-r. Plate VIT, fig. 1. 

Text-fig. 6. 

1847. Lima hai-a, ^-1. d'Orhujny. Pal. FraD9. Terr. Crt't.,vol. iii, p. 54(3, pi. ccccxix, 

figs. 1 — 4. 
1850. — — A. d'OrhiijHij. Proilr. cle Pal., vol. ii, p. 106. 
— — — H. B. Gdnitz. Das Quadersaudst. oder Kreidegeb. iu Deulscli- 

laud, p. 188. 
1855. — — G.Cotteau. Moll. Foss. de I'Youne, p. lOl. 
1867. — — E. Guerarujer. Album Palcont. de la Sartlie. p. I'.i, pi. xxiv, 

figs. 16, 17. 



' Album Paluont. de la Sarthe ' (1867), p. 18, pi. xxiv, fig. 1. 



LIMA. 



41 



18G9. Lima rapa, F. J. Pldi-t and G. Caminche. Foss. Terr. Crct. Ste. Croix 

(Mater. Pal. Suisse, ser. 5), 
p. 168. 

1871. Radula (Ctenoides) rapa, F. Stoliczka. Palseont. Indica, Cret. Fauna 

S. India, vol. iii, p. 414. 

1872. Lima rapa, H. B. GcinUz. Das Elbthalgeb. in Sachscu (Palteontograpbica, 

vol. XX, pt. 1), p. 20(i, pi. xliii, fig. 4. 

DesciipHuii .— ^\\(A\ moderately and regularly convex, with ovate outline, nearly 
cqudateral, considerably higlaer than long, margins evenly rounded. Umbones 
.^iiiall, pointed, close together. Apical angle about STf. Ears rather large, much 




Fio. G. — Lima (Ctenoides) rapa, d'Orbigny. Upper Greensand, Haldon. British Museum, No. L. 15616. 

Interior of right valve. Natural size. 

higher than long, with fine radial ribs; the anterior ear larger tliau t]i(> posterior, 
the latter with its outer angle obtuse. 

Ornamentation consists of numerous fine radial ribs which diverge slightly from 
a median or nearly median line or sometimes in places from two lines. These ribs 
are slightly raised and rounded, ami are separated by very narrow grooves; 
near the anterior and posterior margins the ribs become nuich narrower and 
sharper, and may bear small pointed projections. The ribs are slightly wavy 
and their course is often more or less sharply deflected where they pass the 
growth-lamella?. Numerous fine linear concentric ridges occur, and also some 
growth-lamellue. 

() 



42 * rRETAf'EOTIH LAMETJ.IBIUNCHTA. 

Measurements : 

(I) (2) (3) 

Length . 66 . 43 . 30 nun. 

Height . 90 . 50 . 41 „ 



'o* 



(1 —3) Upper GreensanJ, Haldou. 



yijfhrifirs. — L. rapa is closely related to L. flivririrafa (p. 41) but the valves 
are less flattened and the anterior part slopes gi'adually to the margin ; the outline 
is more regularly ovate, and the anterior and posterior ribs are much narrower 
than the others. L. rapa is usually considerably larger than L. divaricafa. 

Types. — From the Cenomanian of Coudrecieux and Le Mans. 

Bemarhs. — The presence of this species in English deposits appears to have 
been recognised first by the late Mr. C. J. A. Meyer ; it was rocordod hy Mr. 
Jukes-Browne in 189G. 

Dhinbufhm. — Upper Greensand of Haldon. Cenomanian (Meyer's Bed 10) of 
Dunscombe. 



Lima (Ctenoider) tecta, Goldfuss, 188G. Plate VII, figs. 2, 3. 

1836. Lima tecta, A. Goldfuss. Petref. Germ., vol. ii, p. 91, pi. civ, fit;. 7. 

1837. — FEONDOSA, F. Bujardin. Mem. Soc. gt'ol. de France, vol. ii, pp. 216, 

227, pi. xvi, fig. 10. 
1839. — LAMELLosA, H. B. Gehiitz. Char. d. Schiclit. u. Petref. des siiclis. 

Kreidegeb., pt. 1, p. 23. 
1841. — TECTA, F. A. Bi'imer. Die Versteiu. d. nord-deutsch. Kreidegeb., p. 58. 
1847. — — A. d'Orh'ujny. Pal. Fraii9. Terr. Cret., vol. iii, p. 547, pi. ccccxix, 

figs. 5—8. 
1850. — — H. B. Gcinifz. Das Quadersaudst. oder Kreidegeli. in Poutscli- 

land, p. 188. 

— — — A. d'Orhigny. Prodr. de Pal., vol. ii, pp. 166, 247. 

— — — ?, A. AUh. Geogn.-pal. Beschreib. Umgcb. v. Lemlierg 

(Haidiuger's Naturwiss. Abhandl., vol. iii, 
pt. 2), p. 243. 
? 1852. — — ?, iJ. Kner. Denkschr. d. k. Akad. Wisseuscli. Math.-nat. 

CI., vol. iii, p. 318, pi. xvii, fig. 7. 
1867. — — E. Gueranger. Album Pak'out. de la Sartlie, p. 19, pi. xxiv, 

fig. 11. 
1869. — — E. Favre. Moll. Foss. de la Craie de Lemborg, p. 135. 
1869-70. - —F.J. Pidet and G. Campiche. Foss. Terr. Crct. St<?. Croix 

(Mater. Pal. Suisse, ser. 5), 
pp. 168, 170, 173. 
1871. Radula (Ctenoides) tecta, F. Stoliczka. Palocont. ludica, Cret. Fauna 

S. India, vol. iii, p. 420, 
pi. XXX, fig. 12. 



LIMA. 43 

1872. Lima tecta, H. B. Geiiiilz. Das Elbtlialgeb. in Sachsou (rateontographica, 

vol. XX, pt. 1), p. 206, pi. xliii, fig. 3. 
1877. — —A. Fritsch. Stud, im Gcbieto der biihm. Kreideformat. : II, 

Weisscnberg. u. Maliiitz. Scliicht., p. 130, fig. 113. 

1894. — — B. Limdgren. Mollusk-fauuau i Mammillatus och Mucronaia 

zonema (K. Svcnska Vet.-Akad. Handl., 
vol. xxvi. No. 6), p. 43. 

1895. — — F. Vogel. Hollandiscli. Kreide, p. 18. 

— — cf . TECTA, E. Tiessen. Zeitsclir. d. deutsch. geol. Gesellsch., vol. xlvii, 

p. 474. 
1898. — TECTA, G. Miillor. MoIlusk.Untersen.v. Braunschweig u. Ilsede, p. 27. 
1902. — — M. V. Pdlfij. Mitthcil. a. d. Jahrb. d. k. ungariscli. gcol. 

Anstalt, vol. xiii, p. 275, pi. xx, fig. 5. 

Descrijjtion. — Shell convex, much flattened, sub-ovate, slightly oblique, 
considerably higher than long ; antero-dorsal part sloping steeply to the antero- 
dorsal margin which is rather long and straightened. Umbones small, only slightly 
incurved. Ears rather large, relatively high, the anterior larger than the posterior. 

Ornamentation consists of numerous small radial ribs, which are rounded, and 
smooth or nearly smooth. At fairly regular intervals the course of the ribs is 
interrupted by strong growth-lamelljB, ventrally to which the direction of the ribs 
is sometimes deflected. Growth-lamellae, and sometimes ribs, are present on the 
ears. 

Measurements : 

Length ........ 27 mm. 

Heiffht 39 „ 

From the Cenomauian (Bed 11) of Dunscombe. 



o' 



Affinities. — This species is related to L. dicaricafa (see p. -1-1-), but is 
distinguished by the growth-lamellae, by the ribs not diverging from a median 
line, and by the absence of the fine concentric ridges. Lima essertensis, de Loriol,' 
from the Urgonian, is a similar form but is distinguished by the growth-lamellae 
being more closely placed. 

BemarJi-s. — This species has a considerable stratigrapliical range, extending 
from Lower Cenomanian to Senonian. It has been recognised in France, Holland, 
Scandinavia, Saxony, Bohemia, Hungary, etc. In England it has been found in 
the Cenomanian of Devon only, having been discovered and identified by the late 
Mr. C. J. A. Meyer, and first recorded by Mr. Jukes-Browne. The examples from 
the Arrialoor Group, described by Stoliczka, seem quite indistinguishable from the 
European forms. 

' ' Foss. Corall. Valaug. et Urgoiiien de Mt. Salcve ' (18GG), p. 83, pi. d, fig. 12 ; also in A. Favi-e, 
' Recherch. gcol. Savoie,' vol. i (1867), p. 388, pi. c, fig. 23 ; Pictet and Cauipiche, ' Terr. Crct. St«. 
Croix • (1869), p. 139, pi. clxiii, fig. 7. 



44 CRKTACKOUS LAiMEM J HI! AXCIl I A. 

Types. — From the Senonian of Macstricht. D'Orbigny's specimens came 
from the Cenomanian of Lc Maus and from the Senonian of Tours and Loir-et- 
Cher. 

Distribiifion. — Cenomanian (Bed 11) of Dunsconibe. 



Lima (CrjiNoiDHs) luvauicata, Dajardin, 1837. Plate V'll, figs. 4« — d, 5, <Jn, b. 

1837. Lima divaricata, F. Bujardiii. Mcin. Soc. gcol. Je France, vol. ii, p. 227, 

pi. xvi, fig. 7. 

1840. — ARCUATA, //. B. Geinitz. Cbai". d. Scliirht. u. Petrcf. dos siichs. 

KroiJegeb., jjt. 2, p. 57, pi. ix, fig. 7. 

1841. — DIVARICATA, i^. J. iSiimec. Die Verstein. d. uorJ-deutsch. Kreidegeb., 

p. 58. 
1850. — — .1. d'Oi-hujtnj. Prodr. de Pal , vdI. ii, p. 248. 

— — GRANOSA, /. de C. Sowciiii/ ill F. Dixon. Geol. Sussex, p. 347 (p. 382, 

ed. 2), pi. xxviii, figs. 24, 25. 
1854. — _ /. Mon-ig. Cat. Brit. Foss., ed. 2, p. 171. 

1859. Mytilus':' spectabilis, J. Mailer. Petivf. der Aacheu. Ivroidcf., supple- 
ment., p. 10, pi. vii, tig. 10. 

1870. Lima granosa, F. J. Pirfef and G. Campiche. Foss. Terr. Crct. Ste. Croix. 

(Mater. Pal. Suisse, ser. 5), p. 169. 

— — divaricata, Fidel and Caitipichc. Ibid., pp. 171, 173. 

1871. Kadula (Ctenoides) geanosa, F. Stoliczka. Palieout. ludiea, Cret. 

Fauna S. India, vol. iii, p. 415. 

— — — divaricata, Stuliczlca. Ibid., p. 415. 

1872. Lima divaricata, II. B. Geinitz. Das Elbtbalgeb. in Sacliscn (Pal- 

leontograpbica, vol. xx, i>t. 1), 
p. 205, pi. xlii, tig. 18. 
1889. — — A. Ftitseli. Stud, iin Gebiete der biJhni. Kreidefoiniiil. : 

IV, Teplitz. Scliicht., p. 83, fig. 77. 

— — — E. Holzapfel. Die MoUusk. Aachen Kreide (Paloeon- 

tograpliiea, vol. xxxv), p. 241, 
pi. xxvii, fig. 7. 

1897. — granosa, //. Woodn. Quart Jouru. Geol. Soc, vol. liii, p. 383. 

1902. — divaricata, M. p. Fi'tl/ij. MKtbeil. Jahrb. d. lc. uiigarisch. geol. 

Austalt, vol. xiii, p. 274, pi. xx, fig. 4. 

De.^cript'wn. — Shell convex, flattened, the anterior marginal part sloping 
steeply, the posterior part more gradually ; outline rather variable, more or less 
ovate or aj)proaching to oblong, considerably higher than long, only slightly 
unsymmetrical. Umbones rather small, not much incurved. Ears relatively 
short and high, not sharply limited; the antei-ior larger than the posterior. 

Ornamentation consists of numerous small radial ribs which diverge from a 
median or nearly median line or sometimes in part from two lines forming an 



LIMA. 45 

iuverted W. Tlie ribs are sliglitly i-aiscd and often somewhat wavy or irregular, 
especially near the growth-ridg-es. The ribs and grooves are crossed by numerous 
concentric linear ridges. The ribs are sometimes nodular, the nodules having a 
concentric arrangement. At intervals, usually rather distant and fairly regular, 
distinct growth-lamellsB are seen. 
Measurements : 

(1) (2) (3) 

Length . 37 . 20 . 22 mm. 

Height . 51 . 37 . 32 „ 

(1) Chalk, Newtimber. 

(2) B. mucronata zone, Norwicli. 

(3) H. ■planus zone, Dover. 

Ajjiititles. — See L. {Ctomdcs) nqja (p. 42) and L. {Clcnoulcs) tecta (p. 43). 
7y. divarlcafa also presents some resemblance to Lima Uohapfdi, Hennig,' found 
in the Danian of Faxe. 

Bemarls. — This species has hitherto Ijeen known in England as Lima granosa, 
Sow'erby. After making a careful comparison I feel no hesitation in regarding 
it as identical with the widely-distributed L. dicaricatu, Dujardin. This form is 
comparatively rare in England, and the part of the shell near the umbo is usually 
wanting or imperfectly preserved. 

Type. — From the Chalk (? Lower Senouian) of Touraiue. Sowei-by does not 
mention the locality or the horizon from which he obtained Lima granosa, and I have 
not succeeded in finding the type. 

Distrihntion. — Zone of Terebratulina of Hitchin. Zone of Holastcr planus of 
Winchester, Dover, and Cheveley, Blue Bell Hill, Burham (? II. planus zone).' 
Chalk Rock of Cuckhamsle3^ Zone of Micraster cor-aitguinum of Micheldever. 
Zone of Actinocamax quadratus of Salisbury. Zone of Belemnitella mucronata of 
Salisbury and Norwich. 



Snh-ijrnns — LiMATULA, N. r. W'liod, 1839. 

(' Mag. Nat. Hist.,' new series, vol. iii, p. 2:33.) 

LiM.\ (LiMATUl..\) ToMr.ECKiAXA, d' Orbigiti/, 181-7. I'latc VII, figs. 7a,b, Sa — c,da,b. 

I8i7. Lima Tombeckiana, A. (VOrhignij. Pal. Frany. Terr. Crct., vol. iii, p. 534, 

pi. ccccxv, figs. 13 — 17. 
1850. — — d'Orbigny. I'rodr. de Pal., vol. ii, p. 82. 

' ' Bill. K. Svon.ska Vet. Akad. Kandl .' vol. xxiv. No. 7 (1899), p. 10, pi. i. figs. 1. 2; Ravn, 
• MoUusk. Daumarks KridUli I. Lamollibr. ' (1^02), p. lOO, pi. ii, fig. 15. 



46 (.'UETACKOUS LAMELLl BRANCllIA. 

? 1854. Lima semisulcata, /. MorrU. Cat. Brit. Foss., ed. 2. p. 172 (jjarti7n). 
1855. — ToMBECKiANA, (?. Cutleau. Moll. Foss. de I'Youue, p. 100. 
1861. — — P. de Loriul. Aiiim. Invert. Foss. Mt. Saleve, p. 95, 

pi. xi, fig. 11. 
1869. — — P. de Loriol and V. GiUu'ron. Urgon. infer, de 

Landerou, p. I'J, pi. i, fig. 17. 

— — — F. J. Pictet and G. Campiche. Foss. Terr. Cret. Ste. 

Croix (Matt'r. Pal. Suisse, ser. 5), p. 148. 
1871. Eadula (Limatula) Tombeckiana, F. Stoliczka. Palajont. ludica, Cret. 

Fauna S. India, vol. iii, p. 414. 

— Lima Tombeckiana, W. A. Ooster. Protozoa Helvetica, vol. ii, pp. 104, 

123, 140. 
1883. — — W. Keepintj. Foss., etc., Neoc. Uinvare and Brick- 

hill, p. 111. 

Description. — Shell oval, inflated, higher than long, produced a little more 
anteriorly than posteriorl3\ Umbones rather small, close together. Ears equal. 
Margins of valves roitnded, the posterior with a greater curvature than the 
anterior. 

Ornamentation consists of from 13 to 16 strong, rounded or slightly keeled 
ribs separated by narrow grooves. The ribs are confined to the median part of 
the shell, and the anterior and posterior parts are without ribs. The ribbed portion 
is not quite symmetrically placed, the anterior smooth portion being rather larger 
than the posterior smooth portion. Very fine concentric ridges are present on the 
shell, and may form scale-like projections where they cross the ribs. 

Measurements : 

(1) (2) (1.) (5) ((-) 

Length 9 8 8 7 11 mm. 

Height 12 11 12-5 13 lU 15-5 „ 

(1 — 5) Hytlie Beds, Court-at-Street. 
((3) Lower Greensand, Brickhill. 

Afl'udtles. — Some specimens of L. Tomhcckiana approach very closely L. 
Fittoid from Blackdown and Haldon (sec p. 48), and it is quite possible that the 
latter is only a local variety of the former since some examples found in the Upper 
Greensand of Charmouth and Potterne (Plate VII, fig. 10) seem indistinguishable 
from L. TombecJciana. As a rule L. Tombeckiana differs from L. Fittuni in having 
the ribbed part of the shell more nearly symmetrical in position, in the shell being 
rather longer and rather more convex with the umbonal part more j)ointed, and 
in the ribs being more rounded. 

L. Tomheclciana differs from /;. semisulcata, Nilsson, in being smaller, relatively 
longer, less symmetrical, and with the umbonal part more pointed. In this con- 
nection, however, it should be noted that Hennig ^ considers that specimens which 
1 Eevis. Lamellibr. i Nilsson'a 'Petrific. Suecana' (1897), p. 29. 



LIMA. 47 

he lias seen from the Lower Greensand of Atlicrfield and Blacksransf belono- to 
L. semisulcata. L. TomhecJciana also resembles L. svprajuretisis, Contejean,^ found 
in the Upper Jurassic. 

T]ipe!(. — D'Orbigny does not give the locality of the type, but says that he 
obtained specimens from the Neocomian of Neuchatel, Auxerre, Saint Sauveur, etc. 

DtNtrihiition. — Hytlie Beds of Court-at-Stroet near Lympne. Lower Greensand 
of Brickhill. Teal1)y Tiiinestone (zone of /?. hnnisi-icpinils) of Nortli Willingham. 



TjIma (liTMATrLA) DuPiNMANA, r/'O/'A/r/y/y, 1847. Plate VII, figs. 11 r/ — r. 

? 184-5. Lima semisulcata, E. Forbes. Quart. Journ. Geol. Soc, vol. i, p. 248 

(non semisulcata, Nilssou). 
1847. Lima Dupiniana, A. (VOrhigny. Pal. rran9. Terr. Crct., vol. iii, p. 535, 

pi. ccccxv, figs. 18 — 22. 
18.50. — — d'Orhigny. Prodr. de Pal., vol. ii, p. 81. 

1854. — — J.Morris. Cat. Brit. Foss., ed. 2, p. 171. 

1855. — — 0. Cotteau. Moll. Toss, de rTonne, p. 100. 
1865. — — H. Coqnand. Mon. Aptien de I'Espagne, p. 151. 
1869. — — F. J. Pictet and G. Campiche. Foss. Terr. Cret. Ste. 

Croix (Mater. Pal. Suisse, 
ser. 5), p. 150. 
1871. Radula (Limatula) Dupiniana, F. StoUczka. Pateont. Indica, Cret. 

Fauna S. India, vol. iii, p. 414. 

Non 1883. Lima Dupiniana, A. Frllsch. Stud, im Gcbiete der biihin. Kreideforniat. : 

III, Iscrschicliteu, p. 112, fig. 81. ^ 

BpscripHon. — Shell oval, moderately convex, much higher than long, nearly 
equilateral, with the posterior margin more convex than tlie anterior. Umbones 
very small, pointed, close together. Ears unequal. 

Ornamentation consists of from ten to fourteen very narrow radial ribs, 
usually with sharp summits, separated by broad rounded grooves. Tlic anterior 
and posterior parts of the shell arc without ril)s, and tlio posterior part is con- 
siderably larger than the anterior. Very fine concentric ridges are present, 

Moafurri'mfiifii : 

(1) (2) 

Length . 11 . 8 mm. 

Height . 21 . 14-5 „ 

(1) Tealby Limestone, North Williugliaiu. 

(2) Ferniginous Sands, ShanklLn. 



• ' Kimmcrid. de Monflx'liard ' (1859), p. 351. pi. xxvii, fig. 9 ; de Loriol and Cotteau, ' Portland, 
de I'Yonne ' (1868), p. 20.5, pi. xiv, figs. 1, 2. 



48 rRETAC'EOUS LAMELLTBT^AXriTTA. 

Affinifie.^. — This species is easily distinguished from L. Tomhecliana (see p. 45) 
by its rehitively higher and less inflated form, l)y the narrow ribs, and by the less 
symmetrically placed ribbed area. 

In its narrow ribs L. Dtipiniana resembles L. svhcvrjji'ilatrrnlift, d'Orbigny (see 
page 49) but the ribs in the latter arc distributed over the groatoi- ]iai-t of the 
shell and are more widely separated and more numerous. 

The specimens referred to L. semimdcata by Forbes are poorly i)rescrved, Init 
probably belong to this species. 

Types. — From the Neocomian of MaroUes (Aube) and Saint Sauveur (Yonne). 

Distribution. — Tealby Limestone (zone of li. hrvnsvicensis) of North Willing- 
ham. Ferruginous Sands of Slinnklin. Athcrfiold Beds of "Rcdliill. TTytlio Beds 
of Hythe (.//-/'• Topley). 



Lima (Limati la) Fittoni, <VOyhi,jmj, 1850. Plate VII, figs. 12—14, 15 a—c. 

183C. Lima, semisdlcata, J. de C. Sowerhy. Trans. Geol. Soc, ser. 2, vol. iv, 

pp. 336, 359 (not 129, 158), j.!. 
xi, fig. 10. 
1850. — Fittoni, A. (TOrhifjny. Prodr. de Pal., vol. ii, p. 82. 
1854. — sEMi.suLCATA, /. Morris. Cat. Brit. Pos-s., cd. 2, p. 172 (^partim). 
1869. — — J^. .7. PIrtrl and O. Cnnpichi'. Foss. Terr. Crut. Slo. 

Croix (Mater. Pal. Suisse, 
ser. ■>), p. 166 {partim). 

Descrijdion. — Shell oval, moderately convex, higher than long, slightly in- 
equilateral, with rounded margins, the posterior being more convex than tlie 
anterior. Umbones small, close together. Ears equal. 

Ornamentation consists of from 13 to 15 radial ribs with sharp summits, 
separated by narrow grooves. Pointed projections are present on the summits 
of the ribs, especially near the ventral border of the shell. Tlie auterioi' and 
posterior parts of the shell are without ribs. The riljbed area is nnsymmetri- 
cally placed, and the anterior smooth jiart of tlie shell is considerably smaller 
than the posterior part. Fine concentric ridges are seen on well-preserved 
specimens. 

Measurements : 

(1) (2) (3) (4) (r,) 

Length .10 9 8 8 7 

Height . IG 14 14 13 12-5 
(1, 3 — 7) Upper Greensand, Haldou. 

(2) „ „ Blackdown. 



(••>) 


(7) 


7 


() nnn 


12 


10 „ 



LIMA. 49 

Affinities. — This form was referred hj Roworby (in Fitton) to the Senonian 
species L. >temisHlcata, Nilsson,^ but has been regarded by most later writers as 
distinct from that species, and was named L. Fiffoni by d'Orl)ignj'-. 

L. Fitfoni differs, as a rule, from L. semisulcata in its smaller size, and in having 
the ribbed area less extensive and much more asymmetrical in position, though 
occasionally, however, it is nearly symmetrical. It also appears to differ in 
having a relatively shorter hinge-line and less equilateral form. 

For the relation of L. Fiffoni to L. TumhecHana see p. 46. 

Tyfo. — The type is Lima aomisnlcMfa, Sowerby {iion Nilsson) from the Upper 
Greensand of Blackdown. A specimen in the Bristol Museum is regarded as the 
type, but does not agree very well with the figure. 

Distnbution. — Upper Greensand (zone of Schloenhachia rostrata) of Blackdown 
and Haldon. Cenomanian of Axmouth (Bed 12 of Meyer), Dunscombe (Bed 10), 
and Pinhay. 



Lima (Limatula) suBiEauiLATEiJALi.s, iVOrhigny, 1847. Plate VII, figs. IGa, //, 17. 

1847. Lima sub^siquilateralis, A. d'Orhigny. Pal. Fran9. Terr. Cret., vol. iii, 

p. 558, pi. ccccxxiii, figs. 1 — 5. 
1850. — — d'Orhigny. Prodr. de Pal., vol. ii, p. 167. 

1870. — — F. J. Pidet and G. Campiche. Foss. Terr. Cret. 

Ste. Croix (Mater. Pal. Suisse, 
ser. 5), p. 169. 

1871. Radola (Limatula) s0b.«;quilateealis, F. Stoliczka. Palseont. Indica, 

Cret. Fauna S. India, vol. iii, 
p. 415. 

Description. — Shell oval, or rounded oblong, pointed at the umbones, nearly 
equilateral, about twice as high as long, of moderate convexity. Anterior margin 
less curved than the posterior. Ears equal, smooth, with pointed ends. 

Ornamentation consists of about 20 very narrow ribs separated by jjroad, 
slightly concave, interspaces which are crossed by growth-lines. Ribs are absent 
near the anterior and posterior mai-gins. 

Measurements : 

Length . . . 10 mm. 

Height . . . P-> „ 

Upper Greensand, Warminster. 

Affinities. — See TAma Diqnniana (p. 48) and Limn sj). (p. 52). 
Eemarks.—l have seen only two English examples of this species, both of 

' For references, see p. .'>1 . footnote. 

7 



50 CRETATEOT^S E.\ ^FEI-l-II'.H AXCTTTA. 

wliicli ai'(> iiinro ov less imperfect, l)ut after an examination of specimens of 
L. suhasqnilateralis from Le Mans in the Museum of Palfeontology at Paris I am 
inclined to refer them to that species. Tn the specimens from Le Mans the 
number of rilxs is sometimes greater than is shown in D'Orbigny's figure, also the 
ears may be less sharply separated from the valve, and in one case the hinge-line 
was seen to be relatively longer. 

Types. — From the Cenomanian of Le Mans. The specimens here figured are 
in the British Museum. 

Distnhution. — Upper Greensand (zone of Pecten asppr) of Warminster. 



Lima (Limatit.a) decussata, Goldfuss, 1836. Plate A^TT. figs. ISo, /', 10, 20^/, /*. 

1836. Lima decussata, A. Goldfuss. Petref. Grerui., vol. ii, p. 01, pi. civ, fii^'. 5. 

1837. Plagiostoma granulatdm, W. Hisimjer. Lethtea Suecica, pi. xv, fig. 7. 
1841. Lima decussata, F. A. Bijmer. Die Verstein. d. nortl-deutsch. Kreidegeb., 

p. 55. 
184G. — — A. E. Revss. Die Verstein. dor bohm. Kreidefoi-mat., 

pt. 2, p. 32, pi. xxxviii, fig. 15. 
1847. — SEMisuLCATA, J. Miillcr. Petref. der Aachen. Kreidef., pt. 1, j). 33. 
1850. — DECUSSATA, A. cVOrbigny. Prodr. de Pal., vol. ii, p. 248. 

— — SEMISULCATA, if. Kner. Verstein. v. Lemberg (Haidinger's Natur- 

wiss. Abhandl., vol. iii, pt. 2), p. 29. 

— — DECUSSATA, A. AJfJi. Geogn.-palEeont. Bescbreib. v. Lemberg (Haid- 

inger's Naturwiss. Abhandl., vol. iii, pt. 2), 
p. 241. 

— — SEMISULCATA, AWi. Ibid., p. 242. 

1863. — DECUSSATA, A. V. Stromheck. Zeitschr. d. deutsch. geol. Gesellsch., 

vol. XV, p. 151. 
? — — — S. Placketko. Das Becken von Lemberg (Jahresb. d. 

k. zweite Ober-Gymnas. in Lemberg), 
p. 20, pi. i, fig. 19. 
1866. — — K. A. ZUtel. Die Bivalven d. Gosaugeb. (Doukschr. d. 

k. Akad. d. Wissensch. Wien, vol. xsv), 
pt. ii, p. 105, pi. xvi, fig. 4. 
18G9. — — E. Favre. Moll. Foss. de la Craie de Lemberg, p. 136. 

1870. — — F. J. Bidet and G. Campkhe. Toss. Terr. Crot. Ste. 

Croix (Matc'r. Pal. Suisse, ser. 5), 
p. 174. 

1871. Eadula (Limatula) decussata, F. SioViczha. Palseont. Indica, Cret. 

Fauna S. India, vol. iii, p. 415. 

1888. Lima decuss.'v.ta, A. Peron. L'Hist. du Terr, de Craie, p. 145, pi. i, fig. 18. 

1889. — — E. Hohaffel. Die Mollusk. Aachen. Kreide (Pal«on- 

tographica, vol. xxxv), ji. 242, pi. xxvii, 
fig. 4. 



LIMA. 51 

1000. Lima i>ecvssata., C. Gagel and F. Kaunhowen. Jalivb. d. k. preussisch. gcol. 

Landesanst. fiir 1891», p. 232. 
1902. — — /. F. J. Itacn. Mollusk. i Danmarks Kridtafl. : I. Lam- 

ellibr. (K. Dauske Vid. Selsk. Skrift., 
6 Eajkke, nat. og. math. Afd., vol. xi), 
p. 9G, pi. ii, fig. 11. 
— — — A. Wollemann. Fauna d. Liineburg. Kreidc (Abhandl. 

d. k. preussiscli. gcol. Laudesanst., 
N. F., Heft 37), p. .57. 

Description. — Shell inflated, ovate oi* rounded-oblong, nearly equilateral. Um- 
])ones small. Bars rather small, nearly equal. 

Ornamentation consists of numerous sharp ribs, sej^arated by narrow grooves. 
The ribs become less distinct on the anterior and posterior parts of the shell. 
Numerous fine concentric ridges occur, and sometimes give rise to a tubercular 
appearance on the sunamits of the larger ril^s. 

Measurements : 

(1) (2) (3) (4) (5) 

Length .10 9 7 7 6-5 mm. 

Height . 13-5 12 11 lO'o 9-5 „ 

(1, 2, 4, 5) A. quadratus zone, East Haruham. 

(3) Uintacrinus band, Devizes Road, Salisbury. 



Affinities. — L. semisnlcata, Nilsson,' is distinguished from L. decussuta by the 
ribs being limited to the median part of the shell, and hj the relatively higher 
valves. 

Peron thinks that L. prdinafa, d'Orljigny, may be only a variety of L.decussata. 
It appears to differ from the latter in having the ribs more tubercular and usually 
fewer in number. 

Ti/pe. — From the Senonian of Rinkerode, near Miinster. 

Distribution. — Uintacrinus band of Devizes Road, Salisbury. Zone of Actino- 
caniiLc quadratus of East Ilarnham and Ashley Hill. Zone of IJeleuniilella mucronata 
of Clarendon. 



Li.M.\ (LiM.\TLi,.\) wiNTONENSis, sp. nov. Plate VII, figs. 21 (/,//, 22 'f — d. 

Description. — Shell inflated, ovate, nearly equilateral, pointed dorsally. 
Ornamentation consists of 15 or 10 strong, rounded ribs on the median part of 
the valve only. The ril)s are separated l)y very narrow grooves, and bear many 

1 'Petrif. Suecaua' (1827), p. 2.5, pi. i.\, fig. 3; Hcunig, Kevis. LanicU. i Nilssou's ' Petrif . 
Suecana' (1897). p. 28, i-l. ii, fig.s. II, 17. 



52 UKETACKOUS J.AMKLI.I liKAiXCHlA. 

strong ridges placed concentrically and regularly. Below a growth-ring the 
ridges are sometimes situated more closely together. One or two ril)s at the 
margins of the ri])l)ed area are rather smaller than the others. The parts between 
the ribl)ed area and the anterior and posterior margins of tlic valve arc sniooth 
except for faint growth-lines. 



Memurements ; 














(1) 


(2) 


(3) 


W 


(3) 


Tjcngth 


7 


6 


5-5 


5-5 


5 mm. 


Height 


10 


8 


8 


7-5 


7 „ 



(1) Chalk, Claytou. 
(2 — 5) A. (piadraiiis zoao, Winchester. 

Ajjijutics. — This species is distinguished from L. decussate (p. 50) by being 
more pointed dorsally, by having fewer ribs, which also are rounded and confined 
to the median part of the valve, and by the strong ridges which extend across the 
ribs. 

In outline this species resembles Lima- jH'ctiiinhi, d'Orbigny,' l)ut differs in 
having fewer ribs, in the absence of ribs on the anterior and posterior parts of the 
valves, and in the ribs not being carinated and having ridges across them 
instead of tubercles at the summits. 

This species resembles closely the form figured by Geinitz^ as L. isenmalcalu, 
Nilsson. 

Distribution. — Zone of Actinocama,r ([iiadratux of Winchester. Upper Chalk 
(probably zone of Micraster cor-tcstndinarium) of Kenley. 



LiJiA (^Limatula), sp. Plate Vil, fig. 2'S(i, h. 

Description. — Shell inflated, oval, nearly equilateral. Umbones small. Hinge- 
line relatively long. Ears not sharply limited, nearly equal. 

Ornamentation consists of about 20 narrow ribs, separated by very broad and 
shallow interspaces in which very fine radial ribs may be seen. The ribs anterior 
to the median line are closer together and rather stronger than the others. On 
the parts of the valves next to the ears ribs appear to be absent. 
Measurements : 

Length ........ ()■."> nun. 

Height 1' „ 

' 'Pal. rran9. Terr. Cret.,' vul. iii (1847), p. 572, pi. ccccxxvii, tigs. 15— lU. 
= ' Das Elbthalgeb. iu Sachscu,' pt. 2 (1873), p. 53, pi. xvi, fig. 14. 



LIMA. 53 

Affinities. — In the churiictfi' of its onianieiitation this form ivse-iiihlos Lima unh- 
.ri/uilaferalis, d'Orbigny (see p. I'Jj, fVoni the Cenonianian oi JjcMaiis, but tlie shell 
is not so high, is less pointed in (he umbonal region, and has a longer hinge-line. 

In outline this form resembles the exaiii|ilc figiir(>d b_y Ravn ' as Liiiin Fmrli- 
hammeri, von Hagenow, Imt possesses a miirh largei' iiumlHi' (if ribs. 

Beniarh. — I have seen one specimen only, which is in Di'. Blackinore's 
collection. 

Dtstributioii. — Zone of Bdemiiiidla laucivnatu of Clarendon (Salisbury). 



Siih-ijciins — LlllKA, Tf. (1. Ih-iniit, is.')!. 

(' Italiens Tertiiir-GL'liililc uiid ilircii Uigauisehe Eiusuliliisse,' p. 115.^ 

Lima (IjImea?) ro.MrosiTA (Soiccrhi/), 18o(i. Plate VII, &gs. 2-ia, b, 2bii, b, 26. 

1836. Pecten compositus, /. de C. Sowerhy. Trans. Geol. Soc, ser. 2, vol. iv, 

l)p. 241, 342, pi. .xvii, fij,'. 20. 
1847. LiUA cEHOMAHKasia, A. d'Orhitjny. Pal. Fran^. Terr. Crut., vol. iii, ji. 552, 

pi. ccccxxi, figs. 11 — 15. 
1850. — — d'Orhujnij. Prodr. de Pal., vol. ii, p. 167. 

1867. — — E. Gui'nnuji-r. Albiiui Pak'ont. de la Sartliu, p. 19, 

pi. xxiv, figs. 4, P. 
1870. — — F. J. PicM and G. Campkhe. Foss. Terr. Cri-t. Stc. 

Croix (Matt'r. Pal. Suisse, 
ser. 5), pp. 161, 168. « 

F. Sf(iUci:l-a. Palicout. ludica, Crct. Fauna S. India, 

vol. iii, 1). 416. 
li. Wuidinuller. Jahrb. d. k. proussisfb. geol. Landes- 
anst. fiir 1881, pp. 24, 29. 



1871. 


LiMEA 


— 


1882. 


Lima 


— 


Measurehwidii : 








(1) 


(2) 


Length 


12-5 


11 


Heiofht 


L5 


l;3 



(3) (i) (5) (C) 

l(t 9 9 8 mm. 

II-:) l()-25 10 9-.5 „ 

(1, 3 — 6) Upper Greeusuud, Warminster. 
(2) Rye Hill Sand, Maiden Bradley. 

Affinities. — This form is closely related to Lima ijranuhta (sin; hvlow). The 
oi-namentation appears to have been similar in both cases, but in L. compusila the 
scale-like spines on the ribs are much less perfectly preserved and usually appear 
as tubercles only. In L. composita the shell appears to be rather less obli(|ue and 

1 ' MoUuskerue i Daumarks Kridtaflej. 1. Laiuellibr.' (1902), p. 97, pi. ii, fig. 12. 



54 CRETArEOUS LAMELLIRRAXriIIA. 

more iieaily cnuilatrral tlian in />. grdiiidutit ; the height is also slightly greater 
and the iimbones rather more prominent ; the ribs appear to be narrower and to 
have sharper summits. The smaller convexity of L. compusita mentioned by 
d'Orbigny does not seem to be constant. 

liemarlcs. — An examination of the type of I'ccfoi rumpo!<ifnK, 8owerby, shows 
that it is an example of this species (see Vol. I, p. 188, footnote), and con- 
sequently the specific name composita must take the place of cenomanenKis. 

The French examples Aviiich I have seen are, on the average, larger than the 
English. 

Tijin'S. — The type of L. cciiomanensis came from the Cenomanian of Le Mans. 
The type of Fectcn cuirqHmtm is in the Bristol Museum ; it is labelled 
" Blackdown " but is not siliceous and is more probably from AVarminster. 

DistrUndion, — Upper Glreensand (zone of Pccteii as^wr) of Warminster. Rye 
Hill Sand of Maiden Bradley. I have not seen the specimens recorded in the 
Memoirs of the Geological Survey from the zones of Schlienbachia variait.i and 
Uolanter suhglohosus of Hunstanton. 



Lima (Limea?) granulata (Nilsson), 1827. I'latL' A'll, figs. 27rt — c,28,29a,b. 

1827. Plagiostoma geanulatum, S. Nilssoii.. Petrif. Suecaua, p. '20, pi. 

fig. 4. 
1833. — GRANULosuM, S. Woodwcinl. Geol. Norfolk, pp. 48, 51, 

pi. V, fig. 26. 

1836. Lima granulata, A. Goldfuss. Petref. Germ., vol. ii, p. 89, pi. eiii, tig. 5. 

1837. Plagiostoma granulatum, W. Hisinger. Lethtea Suecica, p. 54 (not the 

figure, pi. XV, fig. 7). 

1841. Lima uuricata, i^. ^J. iWmt'r. Die Versteiu. d. uord-deutscli. Kreidegeb., 

p. 55. 

1842. — granulata, F. v. Hngenoiv. Neues Jahrb. fiir Miu., etc., p. 555. 

1846. — — A. E. Eeuss. Die Versteiu. der biihrn. Kreideformat., 

pt. 2, p. 32, pi. xx.\viii, fig. 21. 

1847. — — A. d'Orhignij. Pal. Fran9. Terr. Cret., vol. iii, p. 570, 

pi. ccccxxvii, figs. 5 — 9. (Named 
L. gratiom on plate.) 

1850. — ~ d'Orbigny. Prodr. de Pal., vol. ii, p. 248. 

1851. — pseudocabdium, inflata et dentata, J. Midler. Petref. der Aaclien. 

Kreidef., pt. 2, jip. 67, 68. 
1855. — GRANULATA, G. Gotteau. Moll. Foss. de rYonne, p. 102. 
1870. — — 0. Schhdcr. Neues Jahrb. fiir Min.. etc., p 950. 

— — — F. J. Field and G. Camj'ichc. Foss. Terr. Cret. Ste. 

Croix (Mater. Pal. Suisse, 
ser. 5), p. 170. 



? _ 
1881 



LIMA. 55 

187G. LiM/r,A ORANULATA, D. Brauns. Zcitsdir. f. d. gesauimt. Naturwiss., 

vol. xlvi, p. 386. 
Lima qranulata, H. Beiclce. Die Tourtia von Miilhcim a. d. Ruhr, p. 27. 
LiMEA GRANULATA, K. A. ZiUeJ. Handh. d. Palceont., vol. ii, p. 27. 

1888. Lima granulata, A. Peron. L'HLst. Terr, de Craie, p. 147. 

1889. LiMEA ORANULATA, O. Griepenhfrl. Senon. von KiJnigslutter (Palseont. 

Abliandl., vol. iv), p. 41. 

— Lima granulosa, E. Uuhapfd. Die Mollusk. Aachen. Kreide (Palffion- 

tographica, vol. xxxv), p. 239, pi. xxvii, 
fig. 6. 

— — guanulata, a. Fritsdt. Stud, im Gobicte der bohm Kreideformat. : 

IV, Teplitz. Schioht., p. 83, fig. 76. 

1893. — — Fritsch. Ibid., V, Priesener Schicht., p. 100. 

1894. — — B. Lnndgren. Molluslc-faiinaii i Mfinuiilll. och Mucron. 

zonerna(K. SveuskaVet.-Akad. Handl., 
N. F., vol. xxvi. No. 6), p. 42. 

1897. — — A. Hennig. Eevis. Lamell. i Nilssou's 'Petrific. Suecana' 

(K. Fys. Siill.sk. i Lund. Hand!., N. F., 
vol. viii), p. 26, pi. ii, figs. 6 — 8. 

1898. — — G. Mailer. Mollusk. d. Untersen. v. Braunschweig u. 

Ilsede (Abhandl. d. k. preussisch. geol. 
Landesanst., N. P., Heft 25), p. 29, pi. iv, 
fig. 6. 

1901. — — A. Wollrmann. Jalirl). d. k. preussisch. geol. Landesanst. 

fiir 1900, vol. xxi, p. 16. 

1902. — — Wollemanii. Liineburg. Kreide (Abhandl. d.k. preussisch. 

geol. Landesanst., N. F., Heft 37), p. 57. 
— — — J. P. J. Ravn. Mollusk i Danmarks Kridtaflej. I. (K. 

Danske Vid. Selsk. Skrift., 6 Ecekke, 
nat. og. math. Afd., vol. xi), p. 101. 

Non 1837. — — F. Bujanlin. Mem. Soc. geol. de France, vol. ii, p. 226, 

pi. xvi, fig. 4 (= L. Meslei, Peron, 1888). 

Description. — Sbell very convex, oval, sliglitly ol)]ique, with rounded outline ; 
height a little greater than length. Apical angle very large. Umbones small, 
incurved, close together. Ears of moderate size, nearly equal, rather low aiid 
long, with a few spiny ribs. 

Ornamentation consists of numerous (usually from 22 to 24) strong ribs with 
sharp summits, separated by narrow furrows. Each rib bears three rows of scale- 
like spines, one row being at the summit and one on each side. The spines are 
placed near together, at regular intervals, and curve upwards from the surface of 
the shell, the terminal parts sometimes becoming quite erect. The middle row is 
rather larger than the rows on the sides. In some cases the spines are represented 
by granules. On the anterior and posterior parts of the shell the ribs may be 



56 rT^ETATEOUR LAMETJJrJTi AXCTTTA. 

smallev tliau clsewluTt', but tlie luiddlo rows of spines are here often relatively 
larger. 

Measurements : 

(I) (2) (-.i) (4) (5) (0) (7) (S) (0-» (10) (in 

LeiiKtli 10 Ti 1-") 11 10 10 10 8 0-:) Ki -Ji mm. 
Heiglit 21 IS Ki ]2-r, 11 lo:) 11 In is r2\- „ 

(1 — 5) li. inncroruita zone, Norwich. 
(0) „ „ Aldorluivy. 

(7) A. quadratus zone, East, Haruham. 

(8) B. mucronata zone, Clarendon. 
(9—11) Chalk of Trimingham. 

Afjhiitles. — The form from the Lower Senonian of Touraine described and figured 
as Lima r/ranulata by Dujardin, is regarded by Peron ' as belonging to another 
species which he names Lima Meslei. Peron states that L. Meslei differs from L. 
granulata in having more numerous ribs ornamented with fine granides of which 
the middle row is not larger than the lateral rows ; further, the ribs disappear on 
the anterior and postei'ior parts of the shell, and the ears are without ornamen- 
tation. 

liiulnla scahrinila, Stoliczka," from the Arrialoor Group, is closely related to 
Lima granulata, but owing to the imperfect preservation of the single valve on 
which the species is founded, an exact comparison is not possible. The ornamen- 
tation, however, seems to differ, since it apparently consists of small tubercles of 
nearly equal size. It has been suggested by Holzapfel and Hennig that Lima 
'pseuducard'uim, Reuss,' may be identical with L. granulata, but the ornamentation 
on the ribs of that species appears to be unknown. 

Bemarks. — This species has been referred to Limea by Brauns, Zittel, and 
Griepenkerl, l)ut later Avriters — Holzapfel, Hennig, and RaAni — retain it in the 
genus Lima since they find no evidence of the existence of a taxodont hinge. 
The specimens which I have seen do not show the hinge. 

The outline of the shell varies to some extent in L. granulata, deiJcndingmainl}^ 
on the obliquity of the valves. The appearance of the ribs varies considerablj' and 
is probably due chiefly to the state of preservation ; in the more perfect specimens 
the terminations of the scale-like spines become erect, in otlici's flic s])ines are 
in llie form of sloping scales, whilst in some cases tliey arc i'c|ircsciitc(l by 
tubci'cles onlv. The iuinil)er of ribs also shows variation. 

'• ' L'Hist. du Terr, de Craie' (1888), p. 148, pi. i, figs. 21—24. 

2 ' Palffiont. Indica, Grot,. Faima S. India' (1871), vol. iii, p. 419, pi. xxx, fij,'. 8. 

s 'Die Vcrstein. der biilim. Krcideformat.' (1846), i)t. 2, p. 33, pi. xxxviii, figs. 2, 3; Geiuitz, 
"Das Elbthalgeb. in Sachsen " (' Paloeontograpliica,' vol. xx, pt. 1, 1872), p. 204, pi. xlii, figs. 14, 1.5 : 
see also Braiuis (1876), Fritsch (1877, 1883), Michael (1893), Leonhard (1897). 



ipaUxontoovapbical Socict\>, 1905. 



A MONOGEAPH 



OF THE 



CRETACEOUS LAMELLIBRANCHIA 



OF 



ENGLAND. 



BY 



HENRY WOODS, M.A. 

UNIVERSITY LECTURER IN PALa:0200LOGT, CAMBRIDOE. 



VOL. IL PART 11. 

Pages 57—96; Plates VIII— XI. 



LONDON: 

PRINTED FOR THE PAL^ONTOGRAPHICAL SOCIETY. 

1905. 



PRINTED BY ADLARD AND SON, LONDON AND DORKINO. 



PTERIA. 57 

This species was figured from the Norwicli Cliiilk In- S. "Woodward (1833) as 
Plaglostoma graniilosum, but apparently he was unaware that it had been previously 
described and figured hj Nilsson under the similar name P. gmniilatum. 
Woodward's figure seems to have been overlooked by later writers. 

Distribution. — Actiuocamax quadyatus zone of East Harnham, Salisljury. . 
B,elemnite1la iwicronnta zone of Alderbury, Clarendon (near Salisbury), and various 
localities near Norwich. Chalk of Trimingham. 



FaHi?7?/— PTERITD.E, Meek. 

Gemis—FTEiuA, J. A. Scojjoli, 1777.' 

(' lutrod. Hist. Nat.,' p. 397.) 

Sub-genus — Oxytoma, Meel; 1864. 

('Check List Invert. Foss., N. America,' jx 39; Meek and Hayden, ' Palaeout. TJ. Missouri,' 1864, 

Part I, p. 79.) 

Pteeia (Oxytoma) Coknueliaa'a {iVOrbigmj), 1840. Plate VIII, figs. 1, 2, 3 <i, b, 4-7. 

1836. AvicuLA MACBOPTERA, F. A. Bomer. Die Verstein. nord-deutsch. Oolitli.- 

geb., p. 86, pi. iv, fig. 5 (uon Avicula. 
macropfera, Lamarck, 1819). 

1841. — — — Die Versteiu. d. uord-deutsch. Kreide- 

geb., p. 64. 

1846. — CoRXUELiANA, ^. crO)7;/(//!;/. Pal. Frau?. Terr. Crct., Vol. iii, p. 471 , 

pi. ccclxxxix, figs. 3, 4. 

1846. — PECTiNATA, rf'OrfcjjfKy. Ibid., p. 473, pi. cccxci, figs. 1 — 3. 

1850. — CoENUELiANA, — Prodi'. de Pal., vol. ii, p. 82. 

1850. — PECTINATA, — Ibid., p. 82. 

? 1868. — CoRNUELiANA, E. Eickwald. Letlijea Kossica, vol. ii, p. 508. pi. 

xxii, fig. 1. 
1869. — — F. J. Pictet a)id G. Caiiipiche. Foss. Terr. Crct. Ste. 

Croix (Mater. Pal. Suisse, ser. 5), 
p. 66, pi. dii, figs. 1 — 4. 
1877. — — G. Buhm. Zcitschr. d. deutsch. geol. Gesellsch., vol. 

xxix, p. 237. 
"r* 1883. — — W. Keeping. Foss., et*., Neoc. Upware aud Brick- 

hill, p. 109. pi. v, fig. 2. 
1884. — — 0. Weerth. Die Fauna des Neoioni. im Teutoburg. 

Walde (Paheout. Abhandl., vol. ii), 
p. 50. 

1 Svn. Avicula, Bruguii-re, 1791. 



58 CRETACEOUS LAMELLTBRAXCHIA. 

1889. AvicuLA iN.EQUiVALVis, G. W. LamiiliKjh. Quart. Journ.Geol. Soc.vol. xlv, 

p. 615. 
1895. — CoRNUELiANA, G. Maag. Zeitschr. der deutsch. geol. Gesellsch., vol. 

xlvii, p. 2G7. 

1895. — — F. Vofjel. Holliiudisch. Kreide, p. 55. 

1896. — — A. WoUemuini. Zeitschr. d. deutsch. j,'eol. Gesellsch., 

vol. xlviii, p. 842. 

1900. — — — Die Biv. ii. Gastrop. d. deutsch. u. 

hoUiiud. Neoeoms (Ahhandl. d. k. 
preussisch. geol. Land., N. P., pt. 
31), p. 52. 

1901. OxYTOMA iN.EQuivALVE cdf. MACROPTERA, L. Waagc'ii. .Talirli. d. k.-k. geol. 

Reiohsaust., vol. li, pp. 12, 
15, pi. i, figs. 7, 14, 15. 

Description. — Shell obliquely oval, roundtHl. Hoiglit a little greater than length. 

Left valve moderately convex. Anterior ear triangular. Posterior ear larger 
and longer than the anterior. Surface of valve with from 12 to 21 main rib.s which 
are rounded, and form projections on the margin of the valve. Between the main 
ribs are broad flat interspaces in the middle of each of which a smaller rib occurs, 
and between these secondary ribs and the main ribs one or more still smaller ribs 
are found. On the middle and posterior parts of the valve the ribs are nearly 
straight, Ijut on the anterior part they curve forward. Similar ribs occur on the 
anterior ear; on the postei'ior ear nuich smaller ribs are pi-esent, and growth 
lines are seen. Fine concentric ridges cross both i-il)s and interspaces. 

Right valve nearly flat, with many small, sometimes irregular ribs, which may 
be alternately large and small. Anterior ear ratlier small, witli a well-marked 
byssal sinus. Posterior ear large, pointed, with small radial riljs. 

Medsurements : 





(1) 


(2) 


(3) 


Length 


26 


24 


] o mm 


Height 


27 


25 


15 „ 



(1, 2) Speeton Clay (D 1), Speetou. 
(3) Claxhy Ironstone, Claxby. 

Affinities. — P. {O.rijtoma) CurniwUdiin is distiuguisheil from tlie other Cretaceous 
species of Oj'ijtoina l)y the broad interspaces on which several smaller ribs occur. 
It belongs to the persistent and variable series of forms, ranging from the Rh;etic 
to the Chalk, of which Ptcria iniequifulvis (Sowerby) is the type, and it is regarded 
by L. Waagen as only a variety of that species. 

In most of the English specimens the main ribs are more numerous but less 
prominent than in the examples figured by d'Orl)igny and by I'ictet and Campiche. 



PTERIA. 59 

But the niiinl)ei' of those ribs A-aries considerably, and our specimens agree per- 
fectly with the figures given by Waagen. The specimens from Faringdon are 
smaller than those found in the Speeton Clay, and they present some resemblance 
to P. pediiuda (see beloAv), Ijut the presence of several smaller ribs in the inter- 
spaces connects them with /'. Corniieliana. 

Types. — From the Hils-thon of Elligser Brink. The specimen from Upwarc 
figured hy Keeping is in the Sedgwick ]\Iuseuni ; it is imperfectly preserved, but is 
probably an example of this species. 

Dlstrihidion. — Speeton Clay (zone of Bclemnites lateralis, D 1) of Speeton. 
Claxby Ironstone (zone of B. hifcralis) of Claxby. Tealby Clay (zone of B.jacnlum) 
of Claxby. Lower Greensand of Faringdon. Gault of Folkestone.' 



Pteeia (Oxytoma) fectinata (Snirrrbi/), 1830. Plate VIII, figs. 8a, I>, 0, 10,,,/,, 

11-1:3, Ua, h. 

1836. AvicuLA PECTiNATA, J. de C. Soirerby. Tiuns. Geol. Soc, ser. 2, vol. iv, iip. 

128, 338, pi. xiv. fig. 3. 
1854. — — /. Morris. Cat. Brit. Foss., ed. 2, p. 163. 

1869. — — F.J. Pidet and G. Campiche. Foss. Terr. Crct. Ste. 

Croix (Mati'r. Pal. Suisse, ser. 5), 

p. 70. 

Nou 1846. — —A. d'Orhljinj. Pal. Fraiu'. Terr. Crut., vol. iii, p. 473, 

pi. cccxci, figs. 1 — 3. 

s 

JJcscii'iiiidn. — Shell small, obli(jueIy oval, with evenly rouiuled margin. Height 
a little greater than length. 

Left valve convex, ornamented with luimerous slender ribs often having sharp 
sunnnits. Frequently the ribs are of two sizes — larger and smaller, alternating in 
a more or less regular manner. But in some cases the ribs near the margin of the 
valve are of equal or nearly equal size. The interspaces are flattened and con- 
siderably broader than the ribs. Anterior ear moderatel}' large, triangular, the 
outer angle nearly- a right angle ; surface with ribs similar to those on the rest of 
the valve. Posterior ear much longer than the anterior, wing-like, with concave 
growth-lines; on the dorsal part a few slender ribs occur but are often indistinct 
or absent near the valve. 

Right valve moderately convex dorsally, flattened ventrally, surface smooth or 
wdth very fine radial and concentric ribs. Posterior ear large, not distinctly limited. 
Anterior ear small. 

' The only specimen seen from this horizon is in the British Museum, No. L. 16,880. 



60 



CRETACEOUS LAMELLTBRAXCHIA. 



leasure meats : 














(1) 


(2) 


(3) 


(4) 


(5) 


Length 


16 


10 


9-5 . 


<) 


8 mm 


Height' 


17 


12 


10 


11 


9 „ 



(1) Hythe Beds (Bari^'atc Stone), St. Katherine's Chapel, Guildford. 
(2 — 5) Folkestone Beds, Folkestone. 

Affinities. — The shell in tliis species is smaller than in /'. ('iiiiiiicVunia (see 
above) ; also the main ribs on the left valve are closer together, more numerous, 
and between them not more than one small ril) is found. The ornamentation on 
the right valve is very much finer than in i'. CornueUana. See also rteria 
[OxijtovM) tenuicustata (below). 

Type. — The type came from the Folkestone Beds of Risborough, but appears to 
have been lost. Another specimen, however, from the same locality is in the 
Fitton Collection in the Museum of the Geological Society. 

Distribiifioii. — Hythe Beds (Bargate Stone) of St. Katherine's Chapel, Guild- 
ford. Sandgate Beds of Parham. Folkestone Beds of Folkestone. Recorded by 
Topley from the Hythe Beds of Hythe. Gault of Folkestone (British Museum, 
No. L, 492G).^ Upper Greensand of Ventnor, and Crook Hill, Cheddington 
(Dorset). 



Pteria (Oxytoma) sp. Plate VIII, fig. \')((, h. 

Some very small examples of a Pterin similar to P. pectiutita are found in the 
Totternhoe Stone of Hitchin. They are not well preserved, but appear to be dis- 
tinguished from P. pectinata by the presence of transverse ribs placed at regular 
distances in the spaces between the radial ribs. 



Pteria (Oxytoma) uubia {Etheri,l<jr), 1S81. Plate VIII, fig. 16 a, h. 

1881. AvicuLA DUBiA, R. Efhi'rid(je. In Penning and Jiikes-Bro-\viie. Greol. Cam- 
bridge, p. 145, pi. ii, figs. 4, 4 IT. 

Remarlcs. — lliis is known only by the tu'o type specimens — one being a right 
valve separated from the matrix, the other a left showing the interior onl}-. The 
surface of the right valve is smooth. Since the exterior of the left valve is mi- 

^ Measured obliquely to the hinge-line. 

* The species recorded from the Gault of Folkestone as Avicula liaiili)nana. d'Orbiguy (see Jukes- 
Browne, ' Cretaceous Rocks of Britain,' vol. i, p. 4(55), is probably Pteria ^lectiiuita. 



PTERIA. Gl 

known, the characters and affinities of this " species " cannot be determined. The 
left valve has a length of (3 mm. 

Types. — In the Sedgwick Museum, (Cambridge. 

Disfribidiou. — Totternhoe Stone (zone of Rolisler siibijlobjsiu) of Burwell.' 



Pteria (Oxytoma) tenuicostata (Burner), 1841. Plate VIII, figs. 17 a-d, 18, 

li)a,b, 20a, h, 21 a, 6, 22, 23. 

1841. AviCTjLA LiNEATA, F. A. Burner. Die Versteiu. d. uord-deutsch. Kreidegeb., 

p. 64, jil. viii, fig. 15 {A. tenuicostata on 
pi. viii). 
1850. — SUBLINEATA, ^. f/'O/'fti'i/Hy. Pi'odr. dc Pal., vol. ii , p. 249. 

1869. — TENUicosTA, F. J. Pidet and G. Campiche. Foss. Terr. Crit. Ste. 

Croix (Matei-. Pal. Suisse, ser. 5), 
p. 73. 
1878. — TENUICOSTATA, /. F. Blake. Proc. Geol. Assoc., vol. v, p. 259. 

1882. — — n. ScJiriider. Zeitsclii-. d. deutscli. geol. Gesellsch., 

vol. xxxiv, p. 271. 
1888. — —A. Peron. L'Hist. du Terr, de Craie, p. 153, pi. i, 

figs. 11, 12. 
1904. — — A.W. Roive. Proc. Geol. Assoc, vol. xviii, p. 266. 

Non 1845. — — A. d'Orbigny, in Murchi8on,deVerneuil, and Keyser- 

litiy. Gl'oI. de la Eussie d'Europe, 
vol. ii, p. 490, pi. xliii, figs. 5 — 7. 
— 1854. — LiMEATA, J. Morris. Cat. Brit. Foss., ed. 2, p. 163. 

Bescriptlon. — Shell oliliijuelv oval, usually longer than high. 

Left valve moderately convex ; with evenly convex margins, except the postero- 
dorsal, which is slightly concave. Ears large, the anterior indistinctly limited, and 
with its outer angle rectangular or slightly obtuse. Posterior ear longer and more 
distinctly limited than the anterior, with the dorsal portion extended and wing- 
like. 

Ornamentation of left valve consists of numerous (sometimes as many as 100) 
narrow, well-mai-ked, evenly rounded ribs separated by broad, flat interspaces. 
The anterior ribs are slightly less prominent than the others ; those near the jdos- 
terior border are often closer together. At the margin of the valve the ribs usually 

1 Another specimen fnun the same locality and ]iorizt>u was described by Etheridge as jlwcit/a 
filaia (Penning and Jukes-Browne, 'Geol. Camb.,' p. 14t, pi. ii, fig. 3). I am unable to accept the 
generic position assigned to this species by Etheridge; it may be an Ostrea, but appears to be closely 
allied to the shell described as Anomia subradiata by Eeuss (' Die Versteiu. der bohm. Kreideformat.,* 
pt. 2, 1846, p. 45, pi. xxxi, figs. 18, 19). The type and three other specimens of Acicu'.a filaia are iu 
the Sedgwick Museiun, Cambridge. 



62 CRETACEOUS LAMELLIBRANCHIA. 

show a more or less regular alternation in size, l)ut sometimes two or three of the 
larger ribs occur in proximity without the intervention of smaller ribs. In some 
cases between the large and small riljs a rib of still smaller size is found. Some of 
the large ribs start from near the umbo ; others start at some little distance from 
it but soon reach the same size as the primary ribs ; still other ribs are intercalated 
at a greater distance from the umbo and do not attain the same size as the 
earlier ribs. The anterior and posterior ribs have a slight curvature ; the others 
are more nearly straight. Occasionally the anterior and posterior ribs have a 
faintly marked nodose appearance. The interspaces are smooth, or have a very 
faintly marked radial ribbing. 'J'he anterior ear is ornamented with ribs similar to 
those on the remainder of the valve, bvit they are of uniform or nearly uniform 
size. The posterior ear is marked with growth-lines parallel to its posterior con- 
cave border ; radial ribs also occur, and are rather larger and more widely separated 
on the dorsal portion than on the part near the junction with the rest of the valve. 

Right valve much smaller than the left ; flattened, liut convex in the median 
dorsal part. Anterior ear with a deep sinus. Posterior ear much larger, but not 
marked off from the rest of the valve. Surface smooth, or with vei-y faint concen- 
tric lines. 

Mcas-urements of left valves : 

(1) (2) 

Length . 27 26 

Height (oblique) 25-5 23 

(1, 8) A. cpiadriifii.< zc>ne, West Haruluiiu. 
(2, 5) „ ,, Coddenhaiii. 

(4) Upper Chalk, Euston Parva. 

(3, 6, 7) „ Wells. 

Affinities. — Pteria danica (Ravn) ' is similar in outline and the general 
character of its ornamentation to Pteria tenuicostata, but appears to be dis- 
tinguished by the possession of fewer ribs and by their aljsence in the neighbour- 
hood of the umbo. 

In the character of its ornamentation P. tennicostata closely resembles P. 
pectinata (see p. 59), but is distinguished by its larger size, relatively greater 
length, and smaller convexity ; also the ribs are more numerous, the ears are 
relatively larger, and the anterior left ear is less distinctly limited. 

The specimen from Simbirsk figured by d'Orbigny (1845) as Avicula tenm- 
costatd differs from that species in the possession of fewer and stronger ribs. It 
was subsequently regarded by d'Orbigny- as an example of Avicula laripes, Morton.^ 

' 'Mollusk. i. Daiimarks Kri.ltaflej,' i. (1902), p. 70, pi. i, figs. 1, 2. 

" 'Prodr. de Pal.,' vol. ii (1850), p. 2i9. 

* ' Synopsis Org. Remains Cret., U.S.' (1834), p. 63, pi. xvii, fig. 5. 



(3) 


(4) 


(5) 


«!) 


(V) 


(8) 


26 


20-5 


19 


19 


l;3-5 


12 mm. 


22 


19 


18 


17 


U-75 


11-25 „ 



PTERTA. 03 

Bemarlcx. — In England this species has, up to the present time, been definitely 
recognised in the Adlnocamux, qnadratus zone only. 

The specimen figured by Romer is relatively higher than most of tlie EiigHsh 
examples, but in other characters tliere is close agreement. 

Pferia scminuda (Dames) ' resembles Pteria tennicostatd, l)ut appears to differ 
in the ribs on the left valve being of more nearly uniform size, and in tlie presence 
of distinct ornamentation on the right valve. 

Type. — The type is stated by Romer to have come from the Lower Chalk of 
Lindner Berg, near Hanover, but according to Dr. J. Bohm the horizon is really 
the quadratns Chalk. 

Distribution. — Zone of Jdinocamax quadrntn.-i of West Harnham, near Salisbury, 
and Sewerby (Yorkshire). Upper Chalk (? A. quadratics zone) of Coddenham 
(Suffolk), Wells (Norfolk), and Ruston Parva (Yorkshire). 



Sub-ijcints — PsEUDOPTER.\, F. B. Meel; 1873. 

(' 6tli Ann. Eep. U.S. Geol. Survey of the Territories,' p. 489; Meek, ' Invert. Cret. and Tert. Poss. 
U. Missouri ' (Eep. U.S. Geol. Survey, vol. ix, 1876), p. 29.) 



PtEBIA (PSEUD0PTER.\.) SUBDEPRESSA {d'Orhijilij), 1350. Plate IX, fig. hi, b. 

1845. AvicuLA DEPEESSA, E. Forbes. Quart. Journ. Geol. Soo., vol. i, p. 247, pi. iii, 

fig. 7 (uou A. depressa, Miinster, 1841). 
1850. — SUBDEPBESSA, A. (VOrhujny. Prodr. de Pal., vol. ii, p. 119. 

1854. — DEPRESSA, /. Morris. Cat. Brit. Foss., ed. 2, p. 163. 

1855. — suBDEPEESSA, G. Cotteau. MoU. Foss. de I'Yonne, p. 104. 

1869. — — F.J. Pidet and G. Campiche. Foss. Terr. Crct. Ste. 

Croix (Mati'r. Pal. Suisse, ser. 5), 
p. 70. 
1871. — — F. Stoliczka. Palseont. ludica, Cret. Fauna S. ludia, 

vol. iii, p. 398. 
Remarks. — This species is very imperfectly known at present. It resembles 
P. Jialdonensis from the L^pper Greensand of Haldon (see below) but is easily dis- 
tinguished by the strong concentric ridges ; it also appears to be relatively louger 
and less convex. 

Type. — In the Museum of the Geological Society (No. 2050). 
Distnbutiou. — Lower Greensand (Crackers) of Atherfield. Recorded by Topley 
from the Atherfield Clay of Peasmarsh and Shalford. 

' • Zeitschr. d. deutseh. geol. Gesellseh.,' vol. xxvi (1874), p. 765, pi. xxi, fig. 3 ; Notling, ' Die Fauua 
d. baltisch. Ccuomau.' (Palseout. Abliaudl., vol. ii, 1885), p. 21, pi. iii, figs. 7, 8. 



? 1846. 


— 


? 1842. 


Gervillia 


? 1845-6. 


AVICULA 


? 1850. 


— 


1854. 





1868. 


— 



64 CRETACEOUS LAMELLIBRANCHIA. 



Pteeia (Pskudopteea) anomala {Soicerlnj), 183G, Plate IX, figs. 2a-d, 3rt, h, 40,1. 

1836. AvicuLA ANOMALA, /. de C. Suwerhy. Traus. Geol. Soc, ser. 2, vol. iv, pp. 

240, 342, pi. xvii, fig. 18. 

— A. E. Beiiss. Die Yerstein. der liiilim. Kreiilefunnat., 
pt. 2, p. 22, pi. xxxii, figs. 1 — 3. 

— H. B. Geinitz. Cliar. d. Seliielit. u. Petref. des siichs. 
Kreidegeb., pt. 3, p. 80, pi. xx, fig. 38. 

— — Griindriss d. Verstein., p. 459, pi. xx, 
fig. 5. 

— — Das Quadersandst. oder Kreidegeb. iu 
Deutsclilaud, p. 170 {partim). 

— J. Morris. Cat. Brit. Foss., ed. 2, p. 163. 

— A. Briart and F. L. Cornet. Descript. Mineralog. Gi'ol. 

et Pal. de la Meule de Bracquegnies (Mem. 
cour. et MJm. des Sav. ctraugers, vol. xxxiv), 
p. 52, pi. iv, fig. 7. 
1869. — — F. J. Pictet and G. Campiche. Foss. Terr. Crct. Ste. 

Croix (Mater. Pal. Suisse, ser. 
5). p. 71. 
1871. — — F. iSfolicxka. Palseout. Indica, Cret. Fauna S. ludia, 

vol. iii, p. 398. 
? 1873. — — H. B. Gelnitz. Das Elbthalgeb. in SacLseu (Pateouto- 

grapliica, vol. xx, pt. 1), p. 207, pi. 
xlvi, figs. 5, 6. 
lyyij. — — Ji, Michael. Zeitsehr. der deutsch. geol. Gesellseh., vol. 

xlv, p. 233. 

Nou 1846. — — A. d'Orhiijnij. Pal. Franc. Terr. Cri't., vol. iii, p. 478, pi. 

cccxcii, figs. 1 — 3. 

— 1850. — — d'Orhigny. Prodr. de Pal., vol, ii, p. 167. 

? — 1877. — — A. Fritseh. Stud, ini Gebiete der bdhm. Kreidefoniiat. : 

II, Weisseuberg. u. Malnitz. Scliieht., p. 
128, fig. 108. 

— 1883. _ _ _ Ibid., Ill, Iserschicht., p. 109. 

Description. — Shell rather large; outline (without the ears) triangular, very 
oblique ; anterior margin convex, forming a rounded angle with the sinuous postero- 
ventral margin. Umbo of left valve pointed, acnte, near the anterior extremity. 
Apical angle about 45°. 

Left valve very convex, with a strong, rounded ridge extending from the 
umbo to the postero-ventral extremity. In front of this ridge the shell curves 
rapidly downAvards, and becomes nearly vertical to the plane of the valves near 
the anterior margin and near the anterior ear. Behind the ridge the valve is 
flattened and slopes dorsally (fig. 2 o) ; l)ut this part is sometimes divided into two 



PTERTA. 65 

by a median step-like fold (fi,n-. '^ (i). A iian'ow ])art adjoining the posterior ear 
slopes rather rapidly. 

Anterior ear of moderate size, convex, much higher than lung. Posterior ear 
large, united to the whole of the postero-dorsal margin of the valve ; posterior 
margin of ear slightly concave or sinuous, forming an obtuse angle with the hinge- 
line and also with tlie postero-ventral margin. 

Ornamentation consists of numerous radial ril)s whieli are straight or slightly 
nndidating, and extend over the larger part of the valve. On the posterior ear the 
ribs are narrow and separated by broad, flat or slightly concave interspaces. On 
the flattened part of the valve the ribs are rather more rounded and become less 
distinct towards the postero-ventral margin in large specimens. In front of the 
main ridge the ribs are closer together and the interspaces very nari'ow ; on the 
anterior part of the valve and on the anterior ear, ribs are either absent oi- 
indistinct. Numerous, close-set, regular, concentric linear ridges cross both ribs 
and interspaces. 

In small specimens (figs. 4ii, h) having the ornamentation well preserved, the 
ribs on the flattened part of the valve are naiTOw, rounded, distinctly limited, 
and separated by I)road interspaces; new ribs are introduced in the middle of 
some of the interspaces. The ribs and interspaces are crossed at regular intervals 
by concentric ridges which form squares or oblongs with the ribs. On the posterior 
ear similar ornamentation occurs, )iut the concentric ridges cut the ribs obliquely. 

Right valve not seen. 

MeasurcinriitK : 

(1) (2) 

ITml)0 to postero-ventral extremity 80 . . 75 mm. * 

Length of hinge-line ... 49 . . 54 ,, 

(1, 2) Blackdowu. 

Affinities. — The specimen from the Cenonianian of Le Ahms figured l)y 
d'Orbigny as Arinihi anoviuda appears to be distinct from Sowerby's species on 
account of its larger apical angle and its fewer, stronger, and moi-e spiny ribs. See 
also 1\ {Pi^endoptpm) haldovensis (below). 

The character of the hinge in this and the other species here included in the 
sub-genus I'seudoptera is unknown ; consequently their systematic position cannot 
be regarded as definitely determined. 

BpiiKirh.^The oidy examples Avhich 1 have seen are the type specimen, six 
specimens in the British Museum, and two in the Museum of Practical Geology. 
Those from Haldon have the ornamentation very perfectly preserved. 

Ti/pe. — In the Bristol IMuseuui, from Blackdown. 

Disfnbntiuii. — Upper Greensand (zone of ScJda'ubachia rostrata) of Blackdown 

and Haldon. 

9 



66 CRETACEOUS LAMELLIBRANCHIA. 

Ptehia (Pseudoptkka) iiAi.iioNENSis, sp. iiov. Plate IX, figs. 5, Cxiji, 7, 8 a-c, 0, 10. 

Description. — Shell of moderate size, triaiigulai-, very oblique. Anterior margin 
slightly convex, forming a rounded angle witli the postero-ventral margin. Umbo 
pointed, acute, near the anterior extremity. Apical angle about 43°. 

Left valve very convex, with a sharp carina extending from the innbo to the 
postero-ventral angle. The part of the valve in front of the carina is bent 
sharply downwards along its whole length, and is ornamented witli from ten 
to eighteen slender, linear ribs, which are separated by l)road flat interspaces. 
The number of rilis increases with age (nving to the intercalation of new ribs 
in the interspaces. The space between the carina and the first rib, and 
sometimes also between the first and second lib, is greater than the space 
between the ribs near the middle of the anterior part of the valve. jVIinute 
spiny projections are present on the riljs in well-preserved specimens. A similar 
but rather stronger rili, also with spiny projections, occurs on the carina. 
Behind the carina two short ribs, extending from near the middle to the margin of 
the valve, are sometimes seen. The larger part of the valve l)eliind the carina is 
flattened and smooth except for numerous, slightly curving growth-ridges, which 
are continued on to the posterior ear, and are sometimes seen in front of the carina, 
where they may Ijecome more prominent. 

Anterior ear small, with rounded margin, indistinctly separated from the 
remainder of the valve, ornamented with radial ribs similar to those on the 
adjoining part of the valve. 

Posterior ear compressed, very large, separated from the remaiudei- of the 
valve by a very shallow depression. Growth-ridges concave and parallel with 
the posterior margin. 

Right valve not seen. 

Measuremcntti : 



(1) 


(-') 


(3) 


(■*) 


(5) 


Height (oblique) . 28 , 


, 20 


. 25 , 


. 23 , 


18 mm. 


Length of hinge-line^ 19 


, ir, 


. 18 


. 15 , 


12 



(1 — 5) Upper Greensand, Hakloii. 

Affinities. — This species is closely allied to Pferia (PsemJoptera) raricosta (Reuss),* 
from the Gosau Beds of St. Wolfgang (Salzburg), but is distinguished by the 
smaller obliquity of the shell, l)y the angle formed by the anterior and postero- 

' This measurement is approximate only, since the posterior wing is usually imperfectly presei-ved. 

- Reuss, 'Char. d. Kreideschicht. iu den Ostalpeu,' etc. (Denkschr. d. k. Akad. Wisseusch. Wien, 
Math.-nat. CI., vol. vii, 1854), p. 147, pi. xxviii, tig. 16; K. A. Zittel, 'Die Bivalven d. Gosaugeb.' 
(Ibid., vol. XXV, pt. ii, 186(3), p. 90, pi. xiii, fig. 6; .4. (jlahra, Geinitz, 'Das Elbthalgeb. iu Sachsen ' 
(Palseontographica, vol. xx, pt. i, 1873), p. 208, jil. xlvi, fig. 7, and pt. ii, pi. xi, fig. 2 ? ; Niitling, ' Die 
Fauna d. baltisch. Cenoman.' (Palieont. Abhaiidl., vol. ii, 1885), p. 22, pi. iii, fig. 9. 



PTERIA. Q7 

ventral margins being smaller, iind by tlie shorter postero-ventral margin. Tt also 
resembles P. {Psen(h>/ifi;-<i) ir/nabenfeims (Lundgren),' from the Senonian of 
Ignaberga. 

P. {P-^cviJdjifrra) liiihlnitcHftix is distinguisla'd from the young of 1'. {J'spiiiloptniv) 
anovKihi (see aboA'e) liy its sharp carina; by the part of the valve behind the carina, 
and the posterior Aving, l)eing smooth; also l)y the strong and more widely sepa- 
rated ribs in front of the carina. 

Types. — In the British Museum and the Sedgwick Museum. 

DistrihvHov. — Upper Greensand (zone of T'erfen asprr) of Haldon. 

Pteeia (Psei'dopteiia) OAUETixA, sp. iiov. Plate IX, figs. 1 1 n, I,, 1-2 ii,h. 

Description. — Shell small, very oblique. Umbo acute, near the anterior 
extremity. Apical angle 2(5° to :^2°. 

Left valve moderately- convex, Avith the median triangular part raiseil but 
flattened ; in front of this the valve bends sharply to the anterior margin ; l)ehind, 
it bends rather sharply to join the posterior ear, which is distinctly demarcated. 
Anterior ear small. Posterior ear moderately large, united to the greater part of 
the postero-dorsal margin of the valve ; its posterior margin concave. 

A few narrow, well-defined radial ribs occur on the anterior part of the raised 
triangular portion and just in front of it. In some cases less distinct ribs with 
spiny pi'ojections are present on the whole of the triangular part of the valve. 
Growth-ridges are often well-marked, and are continued on to the posterior ear. 

Measurements ; 

Hinge-line . . . . .11 unii. 

Height (oblique) . . . . 21 ,, 

Black Veil. 

Affinities. — This species is distinguished from I'tcria {Fscv(hi2)tt'T(() haldonensis 
(see above) by (1) the greater obliquity of the shell, (2) the smaller apical angle, 
(3) the absence of the sharp carina, (4) the distinctly' limited posterior ear. 

Ti/pes. — In the Museum of Practical Geology (No. 10,780) and the Sedgwick 
Museum. 

histrilmtimi. — Gault of Black Vt-n. 

Ptekia (PskuikiI'tei.'a) (■(i:ia'i.i:sc'p:xs (Nilsson), 1827. Plate IX, figs. 13-10, 17",/', 
18, 19a,l>. 

1827. AvicuLA cffiEULESCENS, S. NUsson. Petrif. Suecana, p. 18, pi. iii, fig. 19. 
? 1836. — A. Gold/iisg. Petref . Germ., vol. ii, p. 132, pi. cxviii, 

fia. 6. 



» ' Mollusk. i MammiMus och Mmronata Zonerna i Nordijstra SkSne ' (1894), p. 44, pi. i, tig. 2. 



68 CRETACEOUS LAMELLTBRAXCHIA. 

? 1841. AvicuLA ccERULESCENs, F. A. Bottler. Die Verstein. d. iiurd-deutsch. Kreide- 

geb., p. 64. 
1850. — —A. (VOrhiyii!/. Prodr. .le Pal, vol. ii, p. 249. 

1888. — cjenvLESCEms A. Pi'i-iin. Hist. Terr, de Craie, p. 155, pi. i, fig. 14. 

? 1889. — cffiKXJLESCENs E. Holzap/il. Dip Mollusk. Aachen. Kreide (Palae- 

oiitographica, vol. xxxv), p. 227. 
1897. — — A. Heiuiig. Kevis. Lamell. i Nilssou's 'Petrif. 

Siieeana,' p. 54, pi. iii, figs. 25 — 27. 

Descripfloii. — Shell rather small, ol)lii|ue, triangular. Anterior margin slightly 
convex oi' nearly straight. Umbo rather near the anterior e.xtreinity, sometimes 
curved slightly backwards. Anterior ear small, not distinctly marked off from the 
rest of the valve. Posterior ear large, triangular, its inner margin not limited, its 
posterior margin slightly concave and continuous with tlie postero- ventral margin 
of the valve. Median part of the valve raised, extending obliquely backwards, some- 
times subcarinate anteriorly. In front of this raised part the valve is bent more or 
less sharply; behind, it is compressed gradually. Surface with weak radial ribs, which 
are straight or slightly undulating, and bear small spiny or scaly projections some- 
times close together, sometimes more or less widely separated. The ribs may 
occur on the anterior part only, or may be present over the entire shell, including 
the ears. Often on the anterior part they are closer together than elsewhere. The 
number of ribs and the width of the flat interspaces vary in different specimens. 
New ribs may be introduced in the interspaces at varying distances from tlie umbo. 
In some specimens numerous fine concentric lines are seen. 

Medsaremeuts : 

(1) (2) (3) 

Length . . 11 . 11 , 10 nnii. 

Height . . 13 . 12 . lO-.-) „ 

(1) A. qiiadratus zone. East Hariibain. 

(2) B. miicronata zone, Norwich. 

(3) „ „ Clarendon. 

Apiiiifics. — The imperfect specimen from the Lower Senoniau of Brunswick 
figured by (i. Midler' as Avlcnla sp. may perhaps be an example of P. rirntlescens. 

Avicnla 'jlahru, Reuss," resembles in t'niui /'. c(Cridesceus, but is distinguished 
by the absence of radial ril)s. 

Avicnla subnodosa, Hagenow,'' from tlio Senonian of Riigen, is pcrliaps iden- 
tical with P. cmrulescens, but in tlic absence of a figure of tlie former 1 am unable 
to make a comparison. 

' ' Mollusk. d. Uuterscn. v. Brauusclnvoig u. Ilsedy ' (ls;»8), p. oi*, pi. v, fig. 10. 
2 ' Die Verstein. der bohm. Kreidefonnat.' (1846), pt. 2, p. 22, pi. xx.\ii, figs. 4, 5. 
■■* 'Neues Jahrl), fiir Min.,' etc. (1842), p. 559. 



AUCELLA. 69 

Remarl-s. — The English specimens have the median part of the valve apparently- 
less sharply marked off from the anterior and posterior parts than it is in the 
examples figured by Hennig, but they agree in this respect with the figure given 
by Peron. 

The specimens show some variation in obliquity and in their relative height 
and length. The differences seen in the ornamentation are probably due, in part, 
at any rate, to imperfections in the preservation of the surface layer of the shell. 
Like Peron, I have seen no specimen of the right valve. 

Examples of this species are pi-eserved in the Norwich Museum, in Dr. Black- 
more's collection, and in Mr. Brydone's collection. 

Distribution. — Zone of Actlnocamax quadratus of East and West Harnham 
(Salisbury). Zone of Belemnitella mucronata of Clarendon (Salisbury) and Norwich. 
Chalk of Trimingham. 

Genus — Aucella, A. Keyserlimj, 1846. 

('Eeise iu das Petschora-Laud,' p. 297.) 

Aucella volgensis, Lahusen, 1888. Plate X, figs. 1 a-c, 2 a-c. 

1888. Aucella volgensis, J. Lahusen. Ueber die russiseheu Aucelleu (Mora, du 

Comitc gcol. Euss., vol. viii. No. 1), p. 
38, pi. iii. fi-,'s. 1—17. 

1896. — — A. P. Pavlow. Quart. Journ.Geol. See, vol. Iii, p. 549, 

pi. xxvii, fig. 1. 

1896. — — var. eadiolata, Pavlow. Ibid., p. 650, pi. x.\vii, fig. 2, 

Description. — Shell large, obliquely ovate, nnich liigher than long, moderately 
inflated, with regularly curving margin. 

Right valve of moderate convexity, flattened. Umbo relatively small, and 
curving only slightly. Anterior ear triangular, with n dec]), iiari'ow byssal siiuis. 
Posterior ear indistinctly limited. 

Left valve very convex and rounded, the dorsal portion continued into a large 
and prominent umbo which curves anteriorly, Postero-ventral part of valve pro- 
duced and somewhat compressed. 

Surface of valves with concentric growth-ridges, sometimes produced into 
lamellfe, and forming regular curves. 

Measurements : 

(1) (2) 

Length .... 45 .. 36 mm. 

Height of left valve (oblique) 60 . . 55 „ 
Thickness (lioth valves) . 32 . . 22 „ 
(1, 2) Spilsby Sandstone, Donnington. 



70 CRETACEOUS LAMELLIBRANCHTA. 

Affinities. — The shell in this species is larger, relatively higher, more oblique, 
and less inflated than in .1. Keijserlingiana (see below). The right valve is more 
flattened, and its umbo is only slightly curved. The umbo of the left valve is 
larger and more prominent. 

BemarJcs. — The only specimens I have seen are internal casts from the Spilsb}' 
Sandstone. The example of this species described by Pavlow as var. raiHolata 
shows faint radial ribs on the internal cast of the right valve, and a slight 
depression on the left valve extending from the umbo to the postero-ventral 
margin (Plate X, fig. 2). 

Types. — From the Upper Volga beds of Kaschpur (Simbirsk), Staraja-Rjasan, 
and Olenek. The specimens figured l)y Pavlow are in the Sedgwick Museum and 
are here re-figured. 

Bislriliitiov. — Spilsby Sandstone (zone of Belemnites lateralis) of Donnington. 



AucELLA KETSEELmGiANA, TrautschoU, 1868. Plate X, figs, oa — d, 'ia,h, 5. 

1837. In.oceeamus concentricus, G. Fischer de Waldhetni. Orvctographie clu 

gouvernm. de Moscou, p. 177, 
pi. XX, figs. 1 — 3. 
1846. AxjCELLA CONCENTRICA, vcir. EUGOSA, A. Kei/gerlimj. Eeise in das Petscbora- 

Laud, p. 300, pi. xvi, fig. 16. 
18.50. AvicuLA (Buchia) n. sp., F. Homer. Neues Jalirl). fiir Miu., etc., p. 393. 
1868. AucELLA Keyseelingiana, H. TrautschoJd . Verluiudl. d. russisch-kaiser- 

licli. iiiiueral. Gresellscli. in Peters- 
Imrg, ser. 2, vol. iii, p. 250. 
1874. — CONCENTRICA, var. EUGOSA, F. Totila. Mesozoisch. Yerstein. v. d. 

Kiihu-Iusel (Die zweite deutsch. 
Nordpolf., in 1869, 1870, iinter 
Kapitiin K. Koklcwev), vol. ii, 
p. .503, pi. ii, figs. 2, 3. 

1874. — — var. rugosissima, F. Tmila. Ihid., p. 504, pi. ii, 

fig. 4, 

1875. Perna imbricatus [Beau MS.], J. PhUUpg, Geol. York?;., pt. i, ed. 3, p. 247. 
— — VEN0STULUS [Bean MS.], Phillips. Ibid., p. 247. 

1884. AvicuLA? teutoburgiensis, 0. Weerth. Neocoui. im TeiitoKurg. Walde 

(Palajout. Abhaudl., vol. ii), 
p. 50, pi. ix, fig. 9. 

1886. AucELLA Keyseelingiana, /. Lahuseii. Mem. Acad. Imp. St. Pt'tersbourg, 

ser. vii, vol. xxxiii, No. 7, p. 4. 

1888. — Keyserlingi, J. Lahusen. Ueber die riissischeu Aucelleu (Mt'm. 

Comite geol. Euss., vol. viii. No. 1), 
pp. 21, 40, pi. iv, figs. 18—23. 

1889. Inoceeamus venustulus et imbricatus, G. W. Lamj'luyh. Quart. Journ. 

Geol. Soc, vol. xlv, p. 615. 



AUCELLA. 71 

1896. AucELLA Keyseelingi, a. P. Pavloxc. Ibid., vol. lii, p. 550, pi. xxvii, fig. 3. 

1899. — — G. Maas. Zeitschr. d. deutsch. geol. Gresellscli.,vol. 

li, p. 249. 

1900. — — A. Wollemann. Die Biv. u. Gastrop. d. deutsch. u. 

iKilliiiid. Neoeoins (Alihandl. d. 
k. preussisch. geol. Land., N. F., 
pt. 31), p. 56, pi. ii, figs. 6—9. 

1901. — — J. F. PompecJcj. Neues Jahrb. fiir Min., etc., Beil.- 

Bd. xiv, p. 319, pi. XV, figs. 3, 6. 
8—10, 13, 14, 17, 18, 20, 21. 
1903. — — A. Wollemann. Zeitschr. d. deutsch. geol. G-esellscb., 

vol. Iv, p. 34 (Briefl. Mittcil.). 

Description. — Shell of moderate size, oljlique, with more or Ics.s triangular out- 
line and rounded margins, higher than long, inflated. Umbones prominent, at the 
anterior end of the hinge-line, almo.st touching, curved inwards and forwards. 

Right valve convex in the neighbourhood of the umbo, but usually flattened 
elsewliere. Anterior ear close to the umbones, triangular, convex, narrow where 
united to the rest of the valve, with a deep and narrow bjssal sinus. Posterior 
ear longer, but indistinctly limited. 

Left valve mucli more convex than the right valve, especially in the dorsal part, 
somewhat compressed posteriorly ; greatest convexity between the umbo and the 
postero-ventral extremity. Umbo more prominent than in the right valve. Ears 
indistinctly limited. 

Both valves ornamented with many narrow, concentric lamelhv wliich are 
placed more or less vertically to the surface and are separated by broad, flat 
interspaces. The lamellfe occur at faii'ly regular intervals, but the distance 
between them varies on different parts of the shell. They curve gently on the 
median part of the valve, but bend more sharply in passing on to the anterior 
and posterior parts, where they become closer to one another. The lamellae 
have often disappeared from the parts near the umbones. 

Measurements : 

(1) (2) (3) (4) 

Length . . 31 . 28 . 24 . 18 mm. 

Height . . 39 . o2 . 30 . 24 „ 
Thickness . — . IC . 16 . 12 „ 
(1 — 4) Claxby Ironstone, Claxby. 
Acuities. — See Aucella volgensis (p. 09). 

Ti/pe. — The specimens figured by Pavlow are in the Sedgwick Museum. 
Distribution.— C\a\hy Ironstone (zone of Belenmites lateralis) of Cla.xby. 
Speeton Clay (zone of Delenmites jaciilnm) of Speeton, 



72 CRETACEOUS LAMET.IJHRANCHIA. 

Genvs — Aticei.i.ina, ./. F. I'cinperlj, I'.lOl. 
(' Neues Jalirb. fiir Miii.,' etc., Beil.-Bd. xiv, p. 365.) 

AucELLiNA GRTPH^oiPES (Sowevhy), 183(). Plate X, figs. (3« — il, 7n — r, 8a,li, 

9rt— f, 10— l:]. 

1836. AvicuLA GEYPH.«:oiDES, /. de C. Soiverby. Trans. Geol. Soc, ser. 2, vol. iv. 

pp. 156, 335, pi. xi, fig. 3. 
1841. — — F. A. Bl'imer. Die Versteiu. d. norcl - deutseh. 

Kreidegeb., p. 64, pi. viii, fig. 16. 
1846. Inoceramus Co(iUA>DiANUS, A. (VOrbigny. Pal. Franc. Terr. Crct., vol. iii, 

p. 505, pi. cccciii, figs. 6 — 8. 
1850. _ _ — Prodr. de Pal, vol. ii, p. 139. 

1853. AtrcELLA gryph^oides, A. v. Strombecl-. Zeitschr. der deutseh. geol. 

Gesellsch., vol. v, p. 500. 

1854. AvicuLA — J. Morris. Cat. Brit. Foss., ed. 2, p. 163. 

1856. AucELLA — A. V. Strombeck. Zeitschr. der deutseh. geol. 

GeseUsch., vol. viii, p. 488. 
1864. — -- H. Bolsche. Neues Jahrb. fiir Min., etc., p. 669. 

1869. Inoceeamtis CoQUANDiANrs, F. J. Picfet and G. Campiche. Foss. Terr. Cret. 

Ste. Croix (Mater. Pal. Suisse, 

ser. 5), p. Ill, pi. clx, figs. 9, 10. 

1875. AvicuLA GRYPHJEOiDEs, A. J. J tikes-Brovjne . Quart. Jouru. Geol. Soc, vol. 

xxxi, p. 298. 
1882. — — R. Windmi'iUer. Jahrb. d. k. preussisch. geol. 

Laudesaust. fiir 1881, pp. 20, 21. 
1893. — — A. V. hUroiiihfck. Zeitschr. der deutseh. geol. 

Gesellsch., vol. xlv, pp. 490, 493. 
1895. — — E. Tiessen. Zeitschr. der deutseh. geol. Gesellsch., 

vol. xlvii, p. 478. 
1899. AucELLA CoQUANDi, 1). J. Aiithida. Kreidefoss. des Kaukasus (Beitr. z. 

Paliiout. u. Geol. Osterr.-Ungarns u. 
d. Orients, vol. xii), p. 78. 

1901. AuCELLiNA GRYPH^oiDES, J. F. Pompeckj. Ncues Jahrb. fiir Min., etc., 

Beil.-Bd. xiv, pp. 354, 365, 
pi. xvi, figs. 6 — 8. 

1902. — — A. WoUenitiini. Liiueljurg. Kreide (Abhandl. il. 

k. preussisch. geol. Landesaust., N. F., 
Heft 37). ]). 64, pi. iii, figs. 2, 3. 

Non 1829. Avicula J. de C. Soi'-i'rby. Trans. Geol. Soc, ser. 2, vol. 

iii, p. 119 [Pseiidomoitiitis 
speiu H carta ( Schlotheim) ] . 
? Non 1847. — — J. Midler. Petref. der Aachen. Kreidef., pt. 1, 

p. 29. 



AUCELLINA. 73 

Description. — Shell oval, very obli(|ue, very incciuivalve ; dorsal pai-t of posterior 
margin more or less straightened, the remaining margins forming a regular curve. 

Right valve flattened, but convex near the umbo ; height and length nearly 
equal. Umbo small, near the middle of the hinge-line, curving slightly. Hinge- 
area obtusely triangular. Anterior ear long, triangular, with a very deep, narrow, 
curved byssal sinus on each edge of which is a row of tubercles. Posterior eai- 
usually of about the same length as the anterior ear, but indistinctly limited, with 
the outer angle obtuse. 

Left valve convex, especially the dorsal part, more compressed postero-ven- 
trally, sometimes with a shallow sulcus extending from the umbo to the postero- 
ventral extremity. Dorsal portion of the valve produced into a lai-ge, prominent, 
much curved umbo. Hinge-area obtusely triangular. Posterior car larger than 
the anterior, with a rounded depression between it and the umbo ; anterior ear 
short, triangular. 

Ornamentation consists of numerous concentric growth-lines which sometimes 
become lamellar, and are separated by flat interspaces. Small, close-set, radial 
ribs occur, especially in the neighbourhood of the umbo. 

Measurements of left valve : 

(1) (2) (3) (4)' 

Length . . 22 . 21 . 18 . 14 nnn. 

Height (oblique) 29 . 27 . 25 . 17 „ 

(1 — 4) Cambridf^e Greeusand. 

Affinities. — The probable relationship of this species to Aucella has l)een 
pointed out by von Strombeck, Stoliczka, and .lukes-Browne. Recently its 
affinities to Fseudomonotis and Aucella have been fully discussed by Prof. 
Pompeckj, l)y whom the genus Aucellina has been established to include Avicida 
aptiensis, d'Orbigny, and Avicula (jri/phieoidcs, Sowerby. Anrellina is very closely 
allied to Aucella, but differs from it in the absence of an articulating groove in 
the hinge-area of the left valve. 

Inoceramus Goquandianns, d'Orbigny, was regarded by Jukes-Bi-ownc as identical 
with Aucellina riri/phasoides, and 1 agi'ee with that view. Tlie identity is also suji- 
ported by the fact that Pictet and Campiche referred the specimens fouTid in (lie 
Cambridge Greonsand to Inoceramus Coquandiainis. 

Types. — I have not seen the types; Fitton stated that they were in the 
collection of Mrs. Murchison, and came from the Upper Greeusand of Nurstt^-d 
and Cambridgeshire (? Cambridge Greensand). 

Distribution. — Up])er Gault of Folkestone and Eastbourne. Red Limestone of 
Hunstanton and Speeton. Cambridge Greensand (derived). 

L'^^pper Greensand (zone of 8chlaml>achia mstrata) of Hanqishire, Devizes, and 
near Didcot ; (zone of Fecten asper) of Okeford Fitzpaine and ^Varminster. Cani- 

10 



74 CRETACEOUS LAIilELLIBllANCHIA. 

bridge Grecnsaiicl (indigenous). Cliloritic Marl of Maiden Bradley, Devizes, 
Isle of Wight, Urchfont (Wilts), Holj^bourne (Hants), and Eastbourne. Chalk 
Marl (zone of Schloenbachia varians) of the Isle of Wight, Folkestone, Hunstanton, 
Lincolnshire, and Yorkshire. Totternhoe Stone of Fulbourn and BurweU. Zone 
of Uolaster sulnjlohosus (above Totternhoe Stone) of Eversden (Cambs.). 



Fa,}iUi/—¥E'Rm'DM, Zittel. 
Genus — Geuvillia, M. J. L. Dcfrance, 1820. 

('Diet. Sci. nat.,' vol. xviii, p. 502.) 

Gervii,li.\ sublanceolata (cVOrhiijny), 1850. Plate X, figs. 14 — 10; Plate XI, 

fig. 1. Text figures 7, 8. 

1826. Geevillia aviculoidks, J. de C. Sowerhy. Miu. Couch., vol. vi, p. lO, pi. 

dxi, figs. 1, 2, 3, 5 (not 4), [uou Periia 
aviculoicles, Sowerby, 1814]. 

1845. — — E. Forbes. Quart. Jouru. Geol. Soc, vol. i, p. 24(5. 

— AvicuLA LANCEOLATA, — Ibid., p. 247, pi. iii, fig. 8. 
1850. — SUBLANCEOLATA, A. d'Orhujuij. Proilr. de Pal., vol. ii, p. 119. 

1853. Gervilia alpina, F. J. Pidd and W. Roux. Moll. Foss. Gres verts de 

Geneve, p. 496, pi. xli, fig. 3. 

1854. Gervillia anceps, J. Morris. Cat. Brit. Foss., ed. ii, p. 167. 

— AvicoLA LANCEOLATA, Morris. Ibid., p. 163. 

1858. Gervilia anceps, F. J. Fidet and E. Eenevier. Foss. Terr. Ajitien (Mati'r. 

Pal. Suisse, ser. 1), p. 121 , 
pi. xvii. 
1865. — — H. Coquand. Mon. Aptieu de I'Espague, p. 145. 

1869. — ALPINA, F. J. Firtd and G. Cainpiche. Foss. Terr. Cret. Ste. Croix 

(Mater. Pal. Suisse, ser. 5), 
p. 83, pi. civ, figs. 2—4. 
1902. Gervilleia anceps, F. Freeh. Centralb. fiir Miii.,etc., p. 612 (text-figure). 

Dcticription. — Shell elongate, very oblique, slightly inecjuivalve, the left valve 
rather more convex than the right. Posterior extremity lanceolate, but rounded. 
Postero-dorsal margin slightly sinuous. Antero-ventral marginal parts nearly per- 
pendicular to the plane lictween the valves and slightly concave. Umbones incon- 
spicuous, almost terminal. Only a very small portion of the valve is seen in front 
of each umbo; on the left valve this portion is bounded by a linear depression, but 
on the right valve it is not limited. Tlie median part of each valve is convex, but 
becomes compressed towards the posterior extremity. Between the convex portion 
and the hinge-line (posterior to the umbo) is a long, triangular, compressed, wing- 
like portion, of which tlie inner boundary is not limited, and tlie posterior margin 



GERVILTJA. 



75 



is slightly convex or sometimes almost straight ; on this part the growth-lines are 
convex posteriorly and cnrvc towards the nmbo, except in young specimens where 
tla-y curve posteriorly as thoy approacli the hinge-line. 

Hinge-line long, forming rather less than half the greatest length of the valve, 



I I !>"> 



\SJ 



^S'l 



He^ 



'-/^^'> 




FiQ. 7.—Gernllia suhlanceolata (d'Orbifpiy.) Lower Gieonaaml (Crackers), Athorfiold. Seilj^ict Museum. 
X j. a, left valve ; b, antero-dorsal view of another specimen ; c, left valve of another specimen. 



and making an obtuse angle with the posterior margin. Ligament pits large, 
usually from six to nine in number, placed at nearly equal distances, and usually of 
nearly equal size, except the anterior and posterior, whicli may be smaller than the 
others. 

Surface of valves ornamented with growth-lamellae only. 



(5) 


(0) 


(7) 


(8) 


(9) 


74 


G6 


41 


54 


41mm. 


152 


149 


89 


110 


86 „ 



76 CRETACEOUS r.AMEETJBRANCHIA. 

Measurements : 

(1) (2) (3) (4) 

Hinge-line . . . . 92 86 86 83 
Umbo to posterior extremity 182 200 182 163 

(1 — 7) Crackers, Atherfiekl. 
(8, 9) Greensand, Blackdown. 

Affinities. — Gervillia snhlanceolata is closely allied to G. anceps, Deshayes,' of 
wliicli tlie types are from the Neocomian of Aube. The English specimens have 
usually been referred to the latter species, biit Pictet and Civmi)iclic regarded thcni 
as distinct. 

The characters which separate the two species are (1) tlic antero-ventral mai'giu 
is concave in G. suhhtnceolata, whereas in G. anceps it is slightly convex or almost 
straight; (2) the posterior margin of the posterior wing-like part is convex, or in 
some cases nearly straight, and the growth-lines on tliis part of the shell are convex, 
whilst in G. anceps tlie corresponding margin and growth-lines are concave, and the 
wing-like part is more distinct ; (3) the line of greatest convexity — extending from 
the umbo posteriorly — is near the middle of the valve in G. suhlanceolata, but near 
the antero-ventral margin in G. anceps ; (4) it is possible that G. suhlanceolata is less 
incquivalvo tliaii G. avccps,- but at present tliis point cannot l)e prove<l, since only 
a few specimens of the latter species showing botli vnlvcs liavo ])een Found. All the 
examples known of G. am-c/is appear to l)(^ larger ami to Imvc thicker shells than 
G. t<ul)lauccolitla. 

I'ictetand Campiehe thought that (/. ((iiccps could be distinguished by the second 
and third ligament pits being close together, whereas in G. siilihniccdlafa the pits 
are nearly equidistant. An examination of specimens of the rornicr shows that the 
position of the second and thii'd pits, shown in d'Orbigny's figure, is an indixidiial 
variation," and is not usually found. I'ictet and Cfimpiche mention as another 
distinction the sharp line of se})aration between the posterior wing and the rest of 
the valve in G. anceps; although this feature is shown in d'Orbigny's figure it is not 
evident in the specimens. 

G. suhlanceolata differs from G. cosnenis, de Tjoriol,' in the rapid tapering of 
the shell towards the posterior extremity and in the less extensive development of 
the posterior wing-like part. 

Remarks. — Examples of this species from Atherfiekl were described and figured 
as Gervillia alpina, Pictet and Roux, by Pictet and Renevier and by Pictet and 

• 'Mc'm Soc. gcol. de France,' vol. v (1842), p. 9, pi. x, fig. 3; D'Orbigny, 'Terr. Cret.,' vol. iii 
(1846), p. 482, pi. cccxciv; Pictet and Campiehe, 'Terr. Crut. Ste. Croix' (1869), p. 82, pi. civ, fig. 6. 

2 See Desbayes' fig. 3c. 

•'' The probaliility of this has licen mentioned hy E. G. Skeat and V. Madson, ' Jur. Ncoc. and 
Ganlt Boulder.s in Denmark' (' Dauniarks geol. Undersog.,' vol. ii, No. 8, 1898), p. 163. 

* ' Gault de Cosne' (1882), p. 83, pi. ix, figs. 21, 22. 



GERVILLIA. 



11 



Campiche. The specimen figured by Pictet and Roux is not sufficiently perfect to 
enable us to state whether it is specifically identical with G. sithlduceohi fa, hut since 
Pictet, Renevier, and Campiche were acquainted with the type and other specimens 
of G. alpinn, and had also good specimens from Atherfield, we may feel every 
confidence in their judgment in this matter. 




Fio. ».—GervilUa suhlanceolata {CCOxU^y). Lower Greonsand (Crackers), Atherfield. Sodgivick Museum. 
Eiglit and loft valves of the same specimen, x J. 

A young individual of this species from Atherfield was described and figured 
by Forbes as Avicula. lanceolata. This name, however, had previously been em- 
ployed by Sowerby (1820) for a species from the Lias, and consequently d'Orbigny 
altered the name of Forbes' species to Avicula sublancoolata. Goldfuss (18:30) had 
also used the name Grrnllia Inncmlata for a species from the IMiddle Jvu-assic of 
Wiirttemberg. Since d'Orljigny's name has priority over GerrilHa alpina of Pictet 



78 CRETACEOUS LAMETJJRRAXCHIA. 

and Roux, the species now iiiuler consideration must be known as Gervillia suh- 
lanceolata (d'Orbigny). 

The yonng individuals of G. snblanceolata differ from the adults in that the 
anterior part of the shell is relatively longer and more wing-like, the posterior ear 
is more sharply limited and its growth-lines are concave posteriorly, and tlio valves 
are more unequal (Plate X, figs. 14, 15). 

G. anhlaiiceoJafa belongs to Freeh's ' Group of G. aviciiloides.' Freeh gives a 
figure of the hinge and interioi' of a specimen from Atherfield. 

I am greatly indebted to Professor Douvillc for the opportunity of seeing a 
specimen of Gervillia anceps from Aube, and also for his kindness in comparing (/. 
snhlanccolata with the specimens of G. anceps in the Ecole des Minos, Paris. 

Ti/pes. — One of the specimens figured by Sowerby (fig. 5) is in the British 
Museum ; the others (figs. 1 — 3) cannot be traced. Sowerby's fig. 4 is from the 
Corallian of Shotover, and does not belong to this species. Avicuhi lanceolata, 
Forbes, from the Lower Greensand (pr()bnl)ly Crackers) of Athei'tield, is in tlie 
Museum of the Geological Society (No. 2057). The type of llerrillia dlpinn came 
from the Gaidt of Saxonet. 

Disfrihiifion. — Lower Greensand (('rackers and Fitton's Beds 20 and 15) of 
Atherfield. Atherfield Beds of Sevenoaks. 

Recorded by To]dey from the Atherfield Beds of Haslemere, Peasmarsh, Shal- 
ford, and Redliill ; fi'om the Hythe Beds of Hythe, Lympne, Maidstone, and 
Pull)orough ; and from the Sandgate Beds of Sandgate, Folkestone, and Parliajn. 

Upper Greensand (zone of Srhhvnhncli'oi roi<fr<if(i) of the Tsle of Wight, Black- 
down, and llaldon. 



Gervillia i.tnoulotdes, Forbes, 1845. Plate XI, figs. 2-8. 

1845. Gkrvillia lingtjloides, E. Forbes. Quart. Joiirn. Geol. Soc, vol. i, p. 246, 

pi. iii, fig. 9. 

— AvicuLA EPHEMERA, Forhcs. Ibid., p. 247, pi. iii, fig. 6. 

184G. Gervillia linouloides, A. d'Orhigny. Pal. Fraii9. Terr. Crct., vol. iii, p. 

485, pi. cccxcvi, figs. 1 — 4. 
1850. — — d'Orbigny. Prodr. de Pal., vol. ii, p. 119. 

AviC0LA EPHEMERA, — Ibid., p. 119. 

1854. Gervillia linouloides, J. Morris. Cat. Brit. Foss., ed. 2, p. 107. 

— AvicuLA ephemera, Morris. Ibid., p. 163. 

1858. Gervillia linouloides, F. J. Pidet and E. Renevier. Foss. Terr. Ajitien 

(Mater. Pal. Suisse, ser. 1), 
p. 123, pi. xviii, figs. 3, 4. 

1869. — — F.J.Pictetand G.Campiche. Foss. Tern Cret. Ste. 

Croix (Mater. Pal. Suisse, 
ser. 5), p. 91. 



GERVILLIA. 79 

Description. — Shell small, thin, elongate, compressed, very ol)li(|ue, angular 
anteriorly, truncated posteriorly. Left valve more convex than the right. Um- 
bones almost terminal. Ligament area narrow, with four or five pits, one of which 
is under the umbo. Anterior part of the shell very small, compressed. Median 
part flattened. Postero-dorsal part relatively large, compressed, wing-like. On 
the left valve a rounded ridge extends from the umbo to the postero-veutral angle ; 
below this ridge the shell is bent sharply. 

Surface smooth, or ornamented with concentric lines. 

Measurements : 

(1) (2) (3) 

Length of hinge . . . lo'o . \b . lo mm. 
Umbo to postero-ventral angle 23 . 29 . 25 „ 
(1—3) Crackers, Atherfield. 

Affinities. — G. recta, Meek and Hayden,' from the Fox Hill Beds of the Upper 
Missouri, is closely allied to this species. The imperfectly known Gervillia Reichi, 
Romer,^ resembles G. linguloides, but appears to have the posterior wing more 
distinctly limited. 

In the form of its shell G. Ihujuluides resembles some of the species of Pteria 
which belong to the sub-genus Pseudoptera (see p. 63), but the presence of liga- 
ment pits proves it to be a Gervillia. 

Bemarks. — Pictet and Renevier showed that Avicida ephemera, Forbes, is only 
an internal cast of Gervillia linguloides. 

This species occurs commonly in the Orackers of Atherfield auel is grt'gai-ious. 

Types. — From the Crackers of Atherfield, in the Museum of the Geological 
Society (Nos. 20-iO, 2054). The types of Avicula ephemera, also from Atherfield, 
are in the same collection (Nos. 2051, 2052). 

Distribution. — Lower Greensand (Crackers) of Atherfield. Recorded by Topley 
from the Atherfield Clay of Peasemarsh and Shalford. 



Gi;i!\ iLi.iA AL.i',Rii;.\iis ((S'(*/n/7;//), Isl'.l. i'latc XI, figs. [hi-(l, lOft-//, 11. Te\l- 

figures 9-14. 

1810. MoDiOLA ? Aii^FORMis, /. Soxoerhij. Mill. Coiicli., vol. iii, p. 03, i>l. ccli. 

183.5. Pekna ALiFOBMis, Sowcrbij. Ibid., vol. vi, systematical iudi-x, \>. 243. 

1845. — ALiKFOKMis, E. Forbfs. Quart. Jouru. Geol. Soc, vol. i, p. '2-k), pi. iii. 
fig^^^ _ 

» ' Proc. Acad. Nat. Sci. Pliilad.' vol. xiii (1861), p. 441. F. B. Meek, ' Invert. Cret. and Tert. Fobs. 

U. Missouri ' (187(3), p. 66, pi. xxix, fig. 1 a, b. 

- 'Die Versteiu. d. uord-deutscli. Kreidegeb.' (1841), p. 64, pi. viii, fig. 14 (uamed G. CotUv ou 
pi. viii). 



80 



CRETACEOUS LAMELLIBRANCHIA. 



1846. Geevilia al^efoemis, A. d'Orhiyny. Pal. Frau^. Terr. Crt't., vol. iii, p. 484, 

pi. cccxcv, figs. 1 — 3. 
1850. — — (TOrhiijnij. Prodr. de Pal., vol. ii, p. 82. 

1852. AvicuLA Ehodani, F. J. Pidd and W. lioux. Moll. Foss. Gres verts de 

Geneve, p. 494, pi. xli, 
fig. 2. 
1854. Geevillia al^efuemis, J. Morris. Cat. Brit. Foss., ed. 2, p. 167. 

1853. Geevilia alifoemis, F. J. Fidel and E. Renevier. Foss. Terr. Aptien (Mater. 

Pal. Suisse, ser. 1), p. 
120, pi. xviii, figs. 1, 2. 
1865. — - H. Coquand. Moii. Aptieii de I'Espagne, p. 144. 

1869. — — F. J. Fidd ami G. Cumjnche. Foss. Terr. Crct. Ste. 

Croix (Matt'r. Pal. Suisse, ser. 
5), p. 86, pi. clvi, fig. 1. 
1871. Geevillea — F. Stoliczka. Palseoiit. Indica, Cret. Fauna S. India, 

vol. iii, p. 399. 

Description. — Shell thick, large, much inflated, triangular or rhombic, oblique. 




FlQ. 9.—Gervillia al:i-formis (Soworby). Lowt-r Grucusaud (Crackers), Athorfield. Sedgwick Musuuiu. 
Dorsal view, showing the ligament area of the right valve. Natural size. 

Anterior parts of l)oth valves more or less nearly vertical to the plane of the valves. 
Around the byssal opening the marginal parts of the valves are sometimes concave. 
Umbones near the anterior extremity. Hinge-area large with large ligament pits 
— usually five or six. Numerous narrow transverse teeth. 

Left valve larger and more inflated than the right, with its umbo strongly 
incurved. A very prominent, convex portion extends from the umbo to the 
rounded postero-ventral extremity ; dorsally it bends anteriorly ; ventrally it has 
a slight posterior curvature. Tliis convex part is separated by a .shallow depres- 



GERVILLTA. 



81 



sion from a small anterior portion, and l)y a lineai' depression from a very large 
triangular posterior portion, wliicli is flattened in small specimens but moderately 
convex in older examples. This posterior portion lias a wing-like projection in 
young specimens, but in older forms its posterior border is nearly straight and 
forms an obtuse angle with the hinge-line. 

Right valve similar to the left, but smaller, less convex, with the posterior 
portion more flattened, and with the umbo nut incurved. 

Ornamentation in the adult shell consists of mimerous growth-lamella}. On 
the earlier part of the shell, and in young exam])l(>s, there are :i few rather strong, 
broad, rounded radial rilis with a few smaller ribs between. 




Fio. 10.— Gei-fiHia aJ.T/ormis (Soworby). Loft valve of specimen shown in Fig. 9. x J. 



Measurements 



Length of hinge 
Height (oblique) 



(1) (2) 

97 . 00 
122 .. 130 
(1_3) Crackers, Atherfield. 



(3) 
85 mm. 

116 „ 



Affimties.— This species presents some resemblance to G. nllnjidiensis 
(Matheron') but is more inflated, less inequivalve, and less oblique. 

Pictet and Campiclie regarded the form figured as G. aJxformh by d'Orbigny as 
distinct from Sowerby's G. alseformis, and they believed that the former was limited 
to the Neocomian whereas the latter occurs in the Aptian. Some specimens from 
the Pmia-bed of Atherfield agree almost exactly with d'Orbigny's figure, and I 

1 ' Catal. Fobs, des Bouches-du-Khone ' (1842). p. 175, pi. xxvi, fig. 1 ; Pictet and Campiche, • Terr. 
Crot. Ste. Croix' (18G9), p. 81, pi. civ, fig. 1. 



82 



CRETACEOUS LAMETJJT5RAXCHTA. 



/. 




Fig. 11. — Gervillia nlse/ormis (Sowerby). Right valvp, and uinlio and ligament area of the left valve 

of the siiecimen shown in fif:fs. !>, 10. x J. 





Fios. 12, l.'i. — Gervillia alirformis (Sowerby). Lower Grecnsancl (Craclcers), Atherfield. Sedgwick 
Museum. 12. Left valve. 13. Rii,'ht valve, x J. 



GERVILLIA. 



83 



cannot regard them as more than a variety in which tlic central convex part is 
rather narrower and more elevated than usual (fig. 14). 

Rcinarls. — G. al.'vforinu belongs to Freeh's ^ ' Group of GeroUlia ITarlmanni,' in 
which the shell is obliquely rhombic and has numerous small teeth. 

Young specimens of G. alxformis differ from older examples in having well- 
marked radial ribs, in the valves being less inflated, and in the occurrence of a 
wing-like projection on the posterior ear. They resemble the form described by 
d'Orbigny as Avicula GottahUna, but in the latter the radial ornamentation and 
well-marked posterior wing are retained in the adult state, whereas they soon 
become obsolete in G. ala'formis. I am not accjuainted with the character of the 
hinge of Avicula Guttaldina. 




Fiu. 14.—GervilliaaLv/ormis (Soworhy). Lower Greoiisaiul (/'(.(•Ha-bed), Atherfield. Sedgwick Museum. 

Loft valve of a narrow varioty. x J. 

Ti/pr. — The type cannot be found ; it came from the Lower Greensand (prolj- 
ably the Fenia-hed) of Sandown, Isle of Wight. 

Distribution. — Perna-hed of Atherfield and Sandown. Crackers and Bed 1 1 
(of Fitton) of Atherfield. Atherfield Clay of Haslemcre. Hythe Beds of Hythe 
and Lympne. 



Gervilllv rosteat.v (Soicerbij), 1830. Plate XI, figs. 12 a, A, 13-23. 

183G. Peuna rosteata, /. de C. Sowerbij. Traus. Gool. Soc, scr. 2, vol. iv., pp. 

241, 342, pi. xvii, fig. 17. 
1846. Avicula cenomanensis, A. d'Orbigny. Pal. Fran9. Terr. Orel., vol. iii, p. 

476, pi. cccxci, figs. 11—13. 
1850. — — d'Orbigny. Prodr. de Pal., vol. ii, p. 167. 



1 'Ceutralb. fur Min.,' etx;. (1902), p. 613. 



(4) 


(5) 


18 


15 mm. 


20 


17 „ 



84 CRETACEOUS LAMELI.JBRANCHIA. 

1850. Pkkna eostrata, cVOrhifjnij. Ibid., p. 168. 
1854. Gervillia — J. Morris. Cat. Brit. Foss., ed. 2, p. 168. 
1871. Melina — F. Stoliczka. Palseout. Indica, Crct. Faumi S. India, 

vol. iii, p. 400. 
? 1895. AvicuLA cf. cenomanensis, E. Tiessen. Zeitschr. d. deutsch. geol. Gesellscb., 

vol. xlyii, p. 479. 

Description. — Shell rather small, of moderate convexitj'-, often very oblique, 
triangular. Ventral and posterior margins rounded. Hinge-line long. 

Left valve more convex than the right, with the umbo moderately incurved. 
The large, central, very convex portion is indistinctly separated from the large, 
anterior, triangular, wing-like ear and from a narrow, flattened, obtusely triangular 
posterior part. 

Right valve similar to the left but less convex and with the umbo only slightly 
incurved, and with the anterior ear more distinctly limited. 

Surface of valves with narrow, regular growth-layers. 

Measurements : 

(1) (2) (3) 

Length of hinge . 21 . 20 . 20 . 

Height (oblique) . 25 . 28 . 24 . 

(1 — 5) Greeusand, Blackdowu. 

Affinities. — Avicula cenomanensis, d'Orbigny, from the Cenomauian of Le Mans, 
appears to be identical with G. rostrata. In all the specimens of the latter which 
I have seen, the terminal portion of the posterior wing is more or less imperfect, 
but the growth-lines show that the posterior margin must have had the same form 
as in d'Orbigny's fig. 11. 

Gervillia rostrata presents some resemblance to the young fonn,s of G. alieformis 
(p. 79) but is more oblique and without radial ribs, also the central convex 
portion is less sharply marked off from the lateral parts, and the anterior ear is 
larger. 

G. rostrata is allied to G. tciiuicostala, Pictet and Campiche (see below), but the 
right valve is less flattened, and the concentric ornamentation appears to be less 
developed — this, however, may be due to difference of preservation, since some 
of the Blackdowu specimens are neai'ly smooth whereas others show di.stinct 
concentric ridges. 

Remarks. — This species is moderately common at Blackdowu but is usually 
imperfectly preserved. An example from the Gault of Folkestone, recorded by 
Price as Avicula cenomanensis, is probably referable to this species, but the greater 
part of the shell has disappeared, leaving a mould of the right valve ; the specimen 
is now in the Museum of Practical Geology (No. 1(324). 

The examples of G. rostrata show a considerable amount of variation in ul)li(|uity. 



GERVILLIA. 85 

and some of the less oblique specimens (Plate XI, figs. 17, 18) appear at fii'st 
siglit to be distinct from the more abundant oblicpic forms, but there is a comijlete 
transition between the extremes. 

Didrihation. — Upper Greensand (zone of Schhciihachia roslrata) of Blackduwn, 
Haldon, and ? Devizes. ? Upper Gault (zone xi) of Folkestone. 



Gervilija, sp. Plate XI, figs. 24, 25. 

Specimens from the Ferruginous Sands of Shaiiklin, whicli were collected by 
the late 0. J. A. Meyer aud are now in the Sedgwick Museum, resemble closely 
G. rostrata and G. tenuicostata (Pictet and Campiche),^ but the material at present 
available is hardly sufficient to justify a definite conclusion as to their relationship. 
The specimen from the Lower Greensand of Upware figured l)y Keeping" as 
Perna sp. nov. resembles still more closely some examples of G. rostrata ; the 
original is in the collection of Mr. J. F. Walker. 



Gekvillia Foebesiana, tVOrhigiuj, 184G. Plate XI, figs. 2G, 27. i'late Xli, figs. 1-5. 

1826. Gekvillia solenoides, /. de C. Sowerhy. Mill. Coiicli., vol. vi, p. 1-i, id. dx, 

figs. 1—3 (not 4). 

1845. — — E. Forbes. Quart. Jouru. Geol. Soc, vol. i, \). '2U>. 

1846. — FoBBESiANA, A. cVOrhiijnij. Pal. Trau^. Terr. Crct., vol. iii, p. 

486, pi. cccxcvi, figs. 5, 6. 
1850. — — d'Orbiynij. I'rodr. de Pal., vol. ii, p. 119. 

1854. — SOLENOIDES, J. Morris. Cat. Brit. Poss., ed. 2, p. 168 (jjarliiii). 

1897. — FoRBESiw A, E. B. Newton. Proc. Dorset. Nat. Hist, aud Antiq. 

Field Club, vol. .wiii, p. 87. 

Descrijjliun. — Shell compressed, slender, greatly elongated, sabre-shaped, taper- 
ing posteriorly to a rounded or subtruncate extremity. Dorsal margin slightly 
concave ; ventral margin convex, with a rather greater curvature than the dorsal 
margin. Near the dorsal margin the valves are compressed rather abruj)tly, but 
ventrally to this they are compressed gradually, giving rise to a knife-like edge. 
Umbones terminal, acute. Posterior ear large, triangular, with its dorsal margin 
sti'aight or very slightly concave and its posterior margin curving backwards so as 
to form an acute angle witii the dorsal margin of the valve. The ear is marked by 
fine growth-lines parallel with its posterior border. 

' 'Terr. Crct. Ste. Croix ' (1869;, p. 88, pi. ulvi, figs. 4, 5. 

■ 'Foss. Nooc. Upware aud Brickhill" (1883), p. 109, pi. v, fig. 3. 



86 CRETACEOUS LAMELTJBRANCHIA. 

Surface of valves siiiootli exce])t for growth-i'idges, of wliicli the curved portions 
near the dorsal margin are more distinct than the other jjortions. 

Hinge with small transverse teeth at the anterior end and six or seven long 
narrow obli(|ue teeth near the posterior entl — the latter decreasing m length 
posteriorly. 

Measurements .- 

(I) (2) (3) (4) 

Height' . 31 . 24 . 15 . 8 mm. 
Length- . 182 . 125 . 71 . 35 „ 
(1—4) Gault, Folkestone. 

Affinities. — This species belongs to Freeh's ■' ' Group of (irrrillid solejmidi'i:;.' 

The only locahties given for G. Forhesiana by d'Orbigny ai-(j Shanklin and 
Athcrfield, and apparently liis figured sj^ecimen came from the latter place. All 
the examples from Shanklin are in the form of casts of which the posterior part is 
usually missing; it is consequently difficult to make out their real charactei'S, but 
they probably belong to this species. 

The examples found in the Gault and Upper Greensand differ somewhat from 
the specimen figured by d'Orbigny. In the former the shell is less slender and 
tapers more quickly posteriorly ; the posterior ear, however, agrees with d'Orbigny's 
figure. 

A considerable number of examples of Grrvillin from different localities and 
horizons have been referred by various writers ' to G. solenoides, Defrance,^ but 
without seeing a large collection of those forms it is impossible to determine their 
relationship to one another and to the examples here described. The figures given 
l)y Defrance do not enable us to form a satisfactory idea of the characters of the 
species; in his original account (1820) he gave " He d'Aix" as the locality, but in 
his later remarks (1824) he states that the specimens came from the department 
of Le Manche. 

The Senonian specimens figured by d'Orbigny' as (/. iii-iri(loiiJcs (noii G. 

' From posterior end of liiu^-e-liuo to opposite margin of valve. 
- From umbo to posterior extremity. 

* 'Ceutralb. fiir Miu.,' etc. (1902), p. G15. 

* Sowerby (18-20), Goldfuss (183(J), Iteuss (184(j), Midler (1847), d'Orbiguy (1847), .\ltli (18,50), 
Zittel (1866), Favre (1869), StoUczka (1871), Geiuitz (1873), Brauus (1876), Fritscb (1877-93), 
Niitling (1885), Griepeukerl (1889), Holzapfel (1889), Liiudgreu (1894), Vogel (1895), Midler (1898), 
G. oblonga, Bohm (1885). 

5 'Diet. Sci. nat.,' vol. xviii (1820), p. 503; vol. xxxii (1824), p. 316, pi. Ixxxvi, fig. 6. 

« 'Pal. Fran^. Terr. Crct.,' vol. iii (1846), p. 489, pi. cccxcvii, fig. 2 (aud perhaps fig. 1). Prof. 
M. Boule informs me that the original of fig. 1 cannot be found in the d'Orbiguy collection, aud that 
the original of fig. 2 comes from Valogues (Manche). 



PERXA. 87 

aviculoides, Sowerby) were afterwards ' referred by that writer to G. sohnoides, 
Defrance, whilst the Cenomanian forms from Le Mans, also figured as G. solenoides, 
were named '' G. subaviculoides. 

The examples of G. solenoides from the Senonian of Aachen figured hy Ilolzapfcl ^ 
differ from our specimens of G. Forhesiana in the greater height of the posterior 
ear and in its indistinct separation from the rest of the valve, also in having a larger 
apical angle. 

Ti/pes. — Two of the specimens figured as G. solenoides by Sowerby (figs. 2, 3) 
are in the British Museum and came from Shanklin. Another specimen figured by 
Sowerby (fig. 1), from the Upper Greensand of Lyme Regis, is in the Museum of 
the Geological Society of London (No. 1555), but is not recorded in Mr. Blake's 
" List of Types." D'Orbigny's type of G. Forhesiana apparently came from the 
Crackers of Atherfield, but Professor Boule informs me that the specimen cannot 
now be found in the d'Orbigny Collection. 

Distribution. — Ferna-hed, Atherfield Clay, and Crackers of Atherfield. Fitton's 
Bed 3G of Blackofang. Ferruginous Sands of Shanklin. Atherfield Beds of Peas- 
marsh. Hythe Beds of Pulborough. Sandgate Beds of I'arham Park. 

Gault (zones iii to vii, and viii) of Folkestone. Zone of Ilnjilites interraptus of 
Okeford Fitzpaine (Dorset). Cambridge Greensand (dei'ived). Upper Greensand 
of Blackdown. 



Genus — Perna, J. G. Bnujuiere, 17S0. 
('Encyc. Method., Vers,' vol. i, p. xiii.) 

Peuna Muli-eti, Deshayes, 1842. Text-figure 15. 

1842. Perna MuLLETi, Des/iayes iu A. Leymerie. Mi-m. Soc. gt'ol. de France, ser. 

2, vol. V, p. 8, pi. xi, figs. 
1-3. 
184.5. — — E. Forbes. Quart. Jouru. Geol. Soc, vol. i, p. 246, pi. i, 

figs. 1 — 4. 
1846. — Uvi.i.Eru. A. d'Orbigny. Pal. Fran?. Terr. Crut., vol. iii, p. 4%, pis. 

cccc, cccci, figs. 1 — 3. 
1848. — MuLLETi, C. L. Korli. Paloeontograpliica, vol. i, p. 171, pi. xxiv, 

fit's. 14 — 17. 



' ' Prodr. de Pal.,' vol. ii, 1850, p. 250. 

2 Ibid, vol. iii (1852), p. 72 (index) ; d'Orbigny. 'Pal. Fran?. Terr. CrJt.,' vol. iii (1846), p. 489, 
pi. cccxcvii, figs. 3, 4, 5. Prof. Boule informs me that these ai-e from lie Mans, an.l aiv n.)« in the 
d'Orbigny collection. 

' • Mollusk. Aachen. Kreide' (1889), p. 223, pi. xxiv, figs. 11, 12. 



88 CRETACEOUS LAMELLTBRANCHIA. 

1850. Perna Muletii, A. d'Orh'ujny. Pnxlr. <1p Pal., vol. ii, p. 82. 

1854. — MuLLETi, J. Morris. Cat. Brit. Foss., ed. 2, p. 179. 

1855. — Mdletii, G. Colteau. Moll. Foss. de I'Yonne, p. 106. 

1869. MuLLETi, F. J. Piciet and G. Campiclie. Foss. Terr. Crct. Ste. Croix 

(Mater. Pal. Suisse, ser. 
5), p. 97, i-l. clviii. 

— - — YoB,B^ST, Pictel avd Camjiirhe. ll)i(l., p. H9, pi. clix. 

1871. Medina Muli.eti, F. Stoliczka. Palaeont. Indica, Cret. Fauna S. India, 

vol. iii, p. 400. 

1883. Perna Mulleti, W. Keepimj. Foss. etc., Neoc. Upware aii<l Uritkhill, 

p. 160. 

1884. — — O.Weerth. Die Fauna des Neoeom. im Teutoburg. Wald. 

(Palajont. Abhandl., vol. ii), p. 49. 
1886. — (Mulletia) Mult.eti, P. Fisrher. Manuel de Conch., p. 956, 

fig. 725. 

1895. — MuLLETT, F. Vogel. Hollaudisch. Kreide, \\ 55. 

— — — G. Maan. Zeitschr. der deutscli. geol. Gesellscli., vol. 

xlvii. p. 267. 

1896. — A. WoUemann. Ibid., vol. xlviii, p. 843. 

1900. — — — Die Biv. u. Gastrop. d. deutscli. u. liol- 

liind. Neocoms (Abhandl. d. k. prens- 
sich. geol. Land., N. F., pt. 31), p. 60. 

Description. — Shell largo, thick, compressed, more or less fitiadrilatcral, with 
unequal angles. Hinge-line long. Unibones almost terminal. Anterior part of 
the shell sharply bent, and more or less nearly perpendicular to the plane of the 
two valves ; anterior marginal part more or less deeply concave. From the umbo 
start two strong, broad, rounded folds ; the anterior of these is near the anterior 
margin and curves anteriorly, its extremity forming the aiitero-ventral angle ; the 
posterior fold at first curves ventrally and afterwards posteriorly, and its termina- 
tion forms the postero-ventral angle. The part of the shell behind the posterior 
fold is compressed and flattened and produced into a wing of varying length. 
The junction of the two valves is sinuous, the anterior, the ventral, and the 
posterior margins (between the angles) being concave on the right valve and 
convex on the left. 

The shell is ornamented with distinct growth ridges which bend ventrally in 
passing over the folds and form a semicircular or semi-oval curve near the 
hinge-line. 

Measurements .- 

(1) (2) (3) 

Length of hingc-linc . .128 . 120 . 95 nun. 

Height (from umbo to postero- 
ventral angle). . . 114 . 135 . 130 „ 

(1 — 3) Pern«-bed, Atherfield. 



I'ERXA. 



89 



Affinities. — The forms foiuul in the Lower Greensand of England which had 
been referred to Perna Mullcti by earlier writers were regarded as distinct by 
Pictet and Campiche, and were named by them Perna Forbesi. They considered 
that the latter were distinguished by the more prominent folds, the shorter and 
more deeply concave anterior mai'gin, and the longer posterior wing. An 
examination of a number of specimens shows that these characters are variable, 
and I am led to agree with Wollemann in thinking that the forms described by 
Pictet and Campiche cannot be regarded as more than varieties of a variable 
species. 




Fio. lo.— Perna Midleti, Desliayes. Lower Greensand (Perna-hed), Sandown. Sedgwick Museum. Left 
valve X }. (The posterior win},' is broken. Forbes gives a figure of a specimen in which the wing is 
perfectly preserved.) 

Perna Midleti is tlie type of Fischer's section Mullclia. 

Ti/pe. — From the Neocomian of Veudeuvre. I have not seen the specimens 
figured by Forbes. 

Distribution.— Perna-hed of Athcrfield and Sandown. Atherfiekl Beds of 
Haslemere, Peasmarsh, Sbalford, Redhill, Sevenoaks, and Hythe. llythe Beds 
of Hythe {fide Topley). Lower Greensand of Potton and Upware. Tcalby 
Limestone (zone of B. bninscicensis) of North Willingham. Speeton Clay of 
S pee ton. 



12 



90 



CKETAt!E()LiS LAMELUBRAXfTITA. 



Pehna HicoRDiiANA, iV Orb i(j hi/, IS-l'O. Text-figures lG-1 8. 



184(J. 

1850. 
1854. 
1855. 
1858. 



18(iy. — 



181)9. 
1883. 

1900. 



Perna Kicoedeana, a. d'Orhiijmj. Pal. Fiiiui;. Terr. Crct., vol. iii, p. VJ-i, 

pi. cccxcix, figs. 1 — 3. 

— — d'Orbigny. Prodr. de Pal., vol. ii, j). 82. 

— —J. Morris. Cat. Brit. Foss., ed. 2, p. 179. 

— G. Coiteau. Moll. Foss. do I'Youue, p. 107. 

— — F. J. Pictet and E. Benevier. Foss. Terr. Aptien (Mater. 

Pal. Suisse, ser. 1), p. 125. 

— F. J. Pictut and G. Campiche. Foss. Terr. Crct. Ste. 

Croix (Mater. Pal. Suisse, ser. 
5), p. 93, pi. clvii, fig. 1. 

FiTTONi, Pictet and Camjiiche. Ibid., p. 95, pi. clvii, fig. 2. 
RicouDiANA, W. Keeping. Foss., etc., Neoc. Upware and BrickJiill, 

p. 150. 
RicoEDEANA, A. WoUevHinn. Die Biv. u. Gastrop. d. deutsch. u. 

hoUiiud. Neocoms (Abliaudl. d. k. 

preussisch. geol. Land., N. F., pt. 

31), p. 61. 




Fio. 10. — Pcma Rifordcana, trOrbigny. Lower Cireousaml (Penta-bud), AtliL'i-fiuld. BIiiSL'iim of Practical 
Geology, No. 12351. Left valve, x J. 



Descriftion. — Shell large, tliick, sub-quadrate, compressed; left valve more 
convex than the riglit. Posterior margin sligiitly convex or nearly straight and 
forniiiig with the hingo-line an angle which is rather greater than a right-angle. 



PEHXA. 



91 



Ventral margin curved reo•ular]3^ Dorsal part of anterior margin concave. 
Valves moderately convex near the anterior margin, but flattened clscwliere. 
Dorsal half or more of the anterior marginal parts concave and depressed. Umbones 
sharp, close together, projecting beyond the rest of the anterior margin of the 
valves. 

Surface with growtli-lamella) at more or less regular intervals. 

Mensiiremenf.'^ ; 

(1) (2) (3) 

105 . 91 . 75 mm. 

1 1<» . i(i<; . kh „ 

(1—3) Pernn-hcd, AtlievfieW. 



Length of liinge 
Height of valve 




V- 




Fill. 17. — Perna Ricordeana, (VOrbiijny- Lower Greensand (Pcrno-bed), Atlioifiold. Seilfovick Museum. 
Eight valve and anterior view of both valves, x J. 



Affijiities. — Examples of this species from the Lower Greensand of the Isle of 
Wight were regarded by Pictet and Campiche as distinct from P. li'icordcaim and 
were described as Perna Fittoni. According to those writers the former is 
distinguished from the latter chiefly by the wide separation of the umbones ; this 
separation, however, seems to me to be due to the thickening of the valves in old 
age, such as may be seen not infrequently in GerviUia and other allied forms. 
The postero-dorsal angle of the valve, according to d'Orbigny's figure, appears to 
be rather smaller in P. EkonJmna than in P. Fittoni, but the difference is not 
great, and moreover, the outline of the shell and the size of this angle vary in 
different specimens of P. Fittoni. /'. German i, Pictet and Campiche, is very 
closely allied to P. Ricordeana. 



92 



CRETACKOrS LAMET>LI liHAXrHIA. 



Types. — From tlic Neocomian of Soignelay, near Auxerre. The type of 
P. Fittoni is from the Pen^a -bed of the Isle of Wiglit. 

Distribution. — Lower Grecnsand (Pcj-)m-bed) of Atherfield. Tcalby Liiiu'stone 
(zone of Bdemnites hrunsvicensis) of Nortli AViningliam. 




Fio. 18.—Pcrna Ricordeana, d'Orbigny. Tcalby Limestone, North Willingham. Sedgwick Museum. 
Loft valve, x J. 



Perna Rauliniana, (VOrUgmj, 1846. Plate XII, figs. 6, la, h, 8, 9. 

1846. Pkena Rauliniana, A. d'Orhujny. Pal. Pran9. Terr. Crct., vol. iii, p. 497, 

pi. cccci, figs. 4, 5. 
1850. — — d'Orbigny. Prodr. de Pal., vol. ii, p. 138. 

1852. — — F. J. PicM and W. Bona: Moll. Foss. Grcs verts de 

Geneve, p. 497, pi. xli, fig. 4. 

1854. — — J. Morris. Cat. Brit. Foss., ed. 2, p. 179. 

1855. — ~ G. Cottcav. Moll. Foss. de I'Youne, p. 107. 

1869. — — F. J. Pictet and G. Campichc. Foss. Terr. Crtt. Ste. 

Croix (Mater. Pal. Suisse, ser. 
5), ]). 100, pi. clx, figs. 1, 2. 

Description. — Shell of moderate convexity, valves nearly equal, compressed 
posteriorly, snb-rhomboidal, oblique, much higher than long; postero-ventral 
margin rounded, anterior margin slightly concave, posterior margin slightly convex, 



(3) 


(4) 


(5) 


24 


23 


1 1 111111. 


49 . 


40 


i)o 



PERNA. 93 

forming an olituse angle with the hinge-line. IJmltonnl jinrtion angular. Apical 
angle small. Surface with growth-lines. 
Measurements -.^ 

(1) (2) 

Length . . 35 . 34 . 
Height . . 73 . G9 . 

(1 — 3, 5) Cambridge Greonsand. 

(4) Lower G-ault, Folkestone. 

Affinities'. — This species is closely allied to P. Bicordeana (see above), but 
appeal's to differ (1) in being relatively shorter and higher; (2) in its more obtuse 
postero-dorsal angle ; (3) in the less prominent uinbones ; (4) in the anterior 
marginal parts (near the byssal opening) being less depressed ; (5) in the smaller 
size of the shell. 

Bemarl-s. — This species occurs commonly in the Cambridge Greensand in the 
form of internnl casts; these differ in outline fi-om specimens with the shell pre- 
served on account of the fact that the postero-dorsal part is missing — probably 
owing to the two valves being in contact or almost in contact at this part. Even 
when the shell is preserved, as in specimens from the (xault, some portion of the 
postero-dorsal margin is frequently missing. 

Types. — From the Albian of Avocourt (Meuse) and Escragnolles. 

Bistrihution. — Cambridge Greensand (derived, intornal casts). Lower Gault of 
Folkestone. 



Perna oblonga, /S'ee^ey, 18GL Text-figure 10 a. 

1861. Perna oblonoa, H. G. Seeley. Ann. Mag. Nat. Hist., ser. 3, vol. vii, p. 121, 

pi. vi, fig. 6. 

Remarks. — This species is known only from internal casts, and apparently 
differs from P. Batdiniana in having a larger apical angle and in the smaller angle 
formed by the hinge-line and the posterior margin. Some of the specimens, how- 
ever, agree very closely with the figure of a cast of P. liauliniana given by Pictet 
and Campiche (pi. clx, fig. 2). 

Seeley compared P. ohlonga with P. suhspathulata, Reuss,= and P. lanccolata, 
Geinitz (see below). It is distinguished from the former by its relatively greater 
height, and from the latter by its larger apical angle. 

1 The height in this ease is measured from the umbo to the postero-ventral margin, and the 
length is taken at right angles to tlie height. 

- • Die Verstein. der l.i.lim. Kreideforniat." pt. ii (184*;). {>• 24, pi. xxxii. figs. IC. 17. 



94 



CRETACEOUS LAMELLTBRANGHIA. 



Rounded depressions wliicli are found commonly on the casts of this and some 
other species of /'')•//*' fi'oin tlie Cambridge Greensand are regarded by Seeley as 
evidence of the occurrence of pearls. 

A specimen from the Gault (Plate XII, fig. 10) resembles P. oJiJoinja, but is 
more convex between the umbo and the ])ostero- ventral exti-emity. 

Type. — In the Sedgwick Museum. 

DiMrihuilon. — Cambridge Greensand (derived). 









cnm. Cainbriclf^e Groonsanil (derived). Internal casts. Sedgwick Museum. Natm-al size, 
Eg. E. — A. Pcnia oblonga, Soeley. The Type. — B, c, Perna, sp. (referred to I', lanccolata, Geinitz, 



Fict. 19. -Pf 

except fig ... . . . . 

by Seeley).— D, Perna semielliiitira, Seeley. The Type.— E, Pema, sp. (regarded by Seeley as a variety 
of P. lanceolata, Geinitz) x 'i. — p, Penia, sp. (referred to P. sxibspathulala, Keuss, by Seeley). 



Perna sumiet.uptica, St'clci/, 18C1. Text-figure 19 d. 

1861 . Perna semielliptica, H. G. Seehy. Ann. Mag. Nat. Hist., ser. 3, vol. vii, 

p. 121, pi. vi, fig. 7. 

Bemarlcs. — This is distinguished from P. Rnuliniana (p. 02) by its relatively 
greater length, larger apical angle, and more rounded outline. 



PERN A. 95 



easurements : 












(1) (2) 


(3) 


Length 


. 


58 . 46 . 


32 mm 


Height 


, 


87 . 70 . 


47 „ 




(1 


—3) Cambridge Greeusand. 





Ti/jie. — From the Cambridge Greensand. In the Sedgwick Museum, Cambridge. 
Distrilinf ion— Cambridge Greensand (derived, internal casts). 



Perna, sp. Text-figures 19, a c. 

1861. Perna lanceolata, H. G. Seeley. Auu. Mag. Nat. Hist., ser. 3, vol. vii, 

p. 122. 

Remarks. — This species (figs. 19 i;, c) was referred l)y Professor Seeley to 
Perna lanceolata, Geiuitz,' and it presents a general resemblance to the examples 
figured by Reuss and by d'Orbigny, but is less oblique. No satisfactory com- 
parison, however, can be made, since the specimens from the Cambridge 
Greensand are in the form of internal casts. 

Some examples (fig. 19 e) were named Perna lanceolata, var., by Seeley; they 
differ from Geinitz's species in the postero-ventral part being more produced and 
less rounded, so that the outline of the valve becomes more distinctly quadrate. By 
this quadrilateral outline they are distinguished from P. IianUniana. 

Didrihution. — Cambridge Greensand (derived, internal casts). ^ 



Perna, sp. Text-figure 19 f. 

1861. Perna subspathulata, H. G. Seeley. Auu. Mag. Nat. Hist., ser. 3, vol. 

vii, p. 124. 

Remarks. — Internal casts wei*e regarded by Professor Seeley as examples of 
r. snhspathnlata, Reuss,^ but they appear to dift'er from the latter in their 
greater convexity. The height is less and the length greater than in P. ohlomja. 

Distribution. — Cambridge Greensand (derived).^ 

> ' Das Elbthalgeb. iu Sacbseu,' pt. i (1873), p. 210, pi. xlvi, fig. 8. References to other figures 
ai-e given by Geinitz. 

* ' Die Versteiu. der bohm. Kreidofonnat.,' pt. ii (1846), p. 24, pi. xxxii, figs. 16, 17. 

3 Avicula cuneala, Seeley, may bo a Penm. Perna lissa, P. plana, and P. transverta, Seeley. 
apjjear to be Inocerami. All four come from the Eed Limestone of Huustautou. Seeley, ' Ann. Mag. 
Nat. Hist.,' ser. 3, vol. xiv (1864), p. 277, and vol. xvii (1866), pp. 178, 170. 



96 CRKTACEOUS LA.M KLLI BRAXCHIA. 

Familij—mNmDJE, Giriy. 
Gcnns — Pinna, LimnvuK, 1758. 
('Syst. Nat.,'ed. 10. p. 707.) 
Pinna Riuhnaldina, d'Orliiijinj, 184-1-, Plato XII, figs. 11-15; Plate XIII, fig. 1. 

1839. Pinna kugosa, F. A. Biimer. Die Versteiu. d. uord-deutsch. Oolith.-geb. 

Nachtrag., p. 32, pi. xviii, fig. 37 (uou 
rvgosa, Scblotlieim). 

1841. — — F. A. Burner. Die Verstein. d. nord-deutscb. Kreidegeb., 

p. 65. 

1844. — RoBiNALDiNA, A. d'OrUgnij. Pal. Frau9. Terr. Cre't., vol. iii, p. 251, 

pi. eccxxx, figs. 1-3. 

1845. — KESTiTUTA, E. Forbes. Quart. Journ. Geol. Soc, vol. i, p. 248. 
1850. — RoBiNALDiNA, A. d'0rbi(j7iy. Prodr. de Pal., vol. ii, p. 80. 

— — SUBBOGOSA, d'Orhi(jny. Ibid., p. 80. 

1854. — suLciFEBA, J. Morris. Cat. Brit. Foss., ed. 2, p. 180. 

1855. — ROBINALDINA, G. Cotteau. Moll. Foss. de rYonne, p. 89. 

1858. — — F. J. Pictet and E. JRenevier. Foss. Terr. Aptien 

(Mater. Pal. Suisse, 
ser. 1), p. 117, 
pi. xvi, fig. 5. 

— — — J.ViUanova-y-Piera. Mem. geog.-agric. de Castelluu, 

pi. lii, fig. 17. 
1865. — — //. Cuquand. Mon. Aptien de I'Espagne, p. 143. 

1867. — — F. J. Pictet and G. Cam.piche. Foss. Terr. Crct. Ste. 

Croix (Mater. Pal. 
Suisse, ser. 4), p. 532, 
pi. exxxix, figs. 3-6. 
? 1882. — — P. de Loriol. Gault de Cosne, p. 82, pi. x, figs. 3-5. 

1883. — — W. Keejiing. Foss., etc., Neoc. Upware and Brick- 

biU, p. 110. 

1884. — — 0. Weerth. Die Fauna des Neoconi. im Toutoburg. 

Walde (Palceout. Abbaudl., vol. ii) , p. 48. 
? 1892. — — 0. Behrendsen. Zeitscbr. der deutscb. geol. Gesellscb., 

vol. xliv, p. 25. 
? 1895. — — F. Voijcl. HoUiiudiscb. Kreide, p. 55. 

1896. — — A.Wollemanri. Zeitscbr. der deutscb. geol. Gesellscb., 

vol. xlviii, p. 845. 

1899. — — G. Maas. Zeitscbr. der deutscb. geol. Gesellscb., 

vol. U, p. 248. 

1900. — — A. Wollemann. Die Biv. u. Gastrop. d. deut.scb. u. 

bolland. Neocoms (Abliandl. d. 
k. preussiscb. geol. Laud., N. F., 
pt. 31), p. 70. 



Ipalxontoovaphical Socict\?, 1900. 



A MONOd T{ A p ir 



CRETACEOUS LAMELLIBIIANGHIA 



ENGLAND. 



BY 



HENUY WOODS, M.A. 

UNIVERSITY LECTURER IN PAL.EOZOOI.OGT, CAM8RID0E. 



VOL. TT. PART III. 

PINNIDiE ASTAETIDiE, CAllDITIDJ:, CRASSATELLITIDiE. 

AND CYPEINID.E. 

Paoes 97—132; Plates XII— XIX. 



LONDON: 
PKINTED FOK THE PA L^ONTOU i; A P Jl IC A L SOCIETY. 



J'UINTKl) 1;Y AllLAKD AND SON, LONDON AND DORKINC. 



PINNA. 97 

y 1888. Pinna Eobinaldina, P. Choffaf. Stratigr. et Paleont. d'Angola (Mi'm. Soc. 

pliys. et cVliist. uat. do Goul-vc, vol. xxx, 
No. 2), p. 8(j, pi. V, figs. 4, 5. 

? 1903. — _ 0. Burckhardt. Jura u. Kreidef. d. Cordillere (Palte- 

outographica, vol. 1), p. 7ft, pi. xv, 
figs. C, 7. 

V 100.5. — cf. Eobinaldina, E. Harhort. Fauna d. Schaumburg-Lipije'sclien 

Kreidemulde (Abhandl. d. k. preus- 
sisch. gcol. Landesanst., N.P., Heft 
4.5), p. 47, pi. V, fig. .5 ; pi. vii, 
figs. 2, 3. 

Descrijition. — Shell straight, much elongated; pyramidal, slightly compressed ; 
margins nearly straight; section sub-qnadrangnlar. 

Each valve is divided into two parts, which meet at an angle. The dorsal part 
is smaller and more flattened than the ventral part, and is ornamented with from 
G to 8 or more ribs, which are narrow, strong, and nearly equi-distant. The ribs 
are separated by broad, shallow, rounded depressions ; both depres.sions and ribs 
are crossed by very fine, somewhat irregular, concentric ridges, which sometimes 
give a slightly serrated appearance to the ribs. The ventral part of each valve is 
moderately convex, and its dorsal portion is ornamented with from 5 to 7 radial 
ribs similar to those on the dorsal part of the valve, but decreasing in size ventrally; 
the last one or two of these ribs sometimes become irregular and discontinuous. 
Tliese radial ribs and their interspaces are crossed by fine concentric ridges. The 
ventral portion of the ventral part of the valve is ornamented with strong growth- 
ridges or folds, which curve rapidly in the direction of the unil)o, and form an 
acute angle where they meet the ribs. 

Measurements : 

(1) (2) 

Length . 135 . 94 mm. 

Height . • 49 . 41 „ 

(1) Perna-hvA, Atherfield. 

(2) Crioceras-hcA, Whale Chine. 

Afinifief!. — The figure of P. (jracilis, Phillips,' is not .sufficiently good to enable 
one to form a satisfactory idea of the character of the species, and the type cannot 
now be found. But other specimens from Speeton, although very imperfectly 
preserved, are sufficient to suggest that P. (jracilis is probably identical with P. 
Rohinalilina. 

It is suggested by Pictet and Campiche that P. tetrngona, Sowerby,- from the 

> ' Geol. Torks.' (182ft). P- 122, pi. ii, fig. 22. 

2 'Min. Conch.,' vol. iv (1821), p. 9, pi. cccxiii, fig. 1; Morris, 'Cat. Brit. Foss.,' ed. 2 (1854), 
p. 180; P. subieirMjona, d'Orbigny, ' Prodr. de Pal.,' vol. ii (1850), p. 165; Pletet and Campiche. 
'Terr. Crct. Ste. Croix' (18(37), p. 587; nou P. tdraijuna, Brocchi, 1814. 

13 



98 CRETACEOUS LAMELLIBRANCHTA. 

Uppei' Greensand of Devizes, is probably identical with P. Ilnhinnldina, The 
specimens from Devizes agree with those found at Blackdown in having the folds 
on the ventral part of the valve rather more strongly marked than in P. Robhialdina 
from the Lower Greensand. In other respects the Upper Greensand form does 
not appear to differ from P. RoUnaltUna , and may be regarded as a variety of it, 
P. Eohinaldina var. tetragotia, Sowerby. 

P. Beijncsi, Hebert and Mnnier-Clialmas,' is similar to P. Iiohiunhliiia, but 
apparently differs in that the ribs on the ventral part of the shell are all smaller 
than those on the dorsal part, and do not diminish gradually in size. 

P. cretacea (Schlotheim)- is closely related to 1'. Bobinaldina, but appears 
to be distinguished (1) by tlie ribs covering a larger proportion of the ventral 
part of the shell and being of nearly uniform size, (2) by the growth-lines on 
the ventral part being more nearly straight, (3) by the shell being usually more 
elongate. 

Bemarls. — The specimens of Pin mi fouiul in the Gault of Folkestone and Black 
Ven have usually been named P. tetrar/oua. Their mode of preservation is more 
or less unsatisfactory, OAving to crushing and to the absence of some of the outer 
layers of the shell, but after a close comparison with examples of 7^. Bohinaldina 
from the Lower Greensand I am unable to see any reason for regarding the former 
as specifically distinct from the latter. 

Pictet and Campiche thought that the examples from Blackdown were referable 
to P. Eohinaldina, differing only in having the folds on the ventral part of the shell 
rather more strongly marked. 

The specimens from the Lower Greensand of the Isle of Wight agree well with 
the figures given by Pictet and Renevier and liy Pictet and Campiche. The 
luimber of ribs varies considerably, and in young specimens the apical angle is 
smaller than in oldei' examples. 

A specimen from the Upper Greensand.of Ventnor, which lias been referred'^ 
to P. Eeynesi, Hebert and Munier-Chaltnas, is probably a crushed example of 
P. Eobinaldina. 

Tijpe. — The type of P. riigosa- came from the Hils-conglomerate of Osterwald. 
The type of P. tcfiru/mia, Sowerby, came from the Upper Gi'eensand of Devizes 
and is now in the British Museum. 

Distribution. — Perna-heA, Crackers, and Fitton's Beds 16 and 38, of Atherfield. 

Ferruginous Sands of Shanklin. Atherfield Beds of Redhill, Reigate. Sandgate 

Beds of Parham Park. Lower Greensand of Brickhill. PSpeeton Clay (zone 

of Ihlemnites hrunHvicenais) of Speeton. Gault of Folkestone and Black Ven. 

' 'Aim. Sciences gt'ol.,' vol. vi (1875), p. 118, pi. v, fig. 10. 

- Geinitz, 'Das Elbthalgeb.' (Palceontographica, vol. xx, pt. 2, 1873), p. 54, pi. xiv, figs. 2, 8. 

■* Jukes-Browne, 'Cret. Eocks of Britain,' vol. i (1900), p. 470. 



PINNA. 99 

Upper Greeiisand (zone of Schla;nhachia rodrata) of Blackdown, Devizes, and 
Ventnor.^ 



Pinna, sp. Plate XIII, figs. 2, 3. 

Some specimens of Pinna found in the Gault of Folkestone differ from 
P. liohhidhUna in having smaller and more numerous ribs, wbicli arc crossed at 
regular intervals by narrow concentric ridges. 



Pinna tegdlata, Etherichje, 1881. 

1881. Pinna tegulata, R. Etheridge, ia Penning and JuJces-Browne's Geol. Cam- 
bridge (Mem. Geol. Survey), p. 142, pi. i, 
fig. 2. 

Bemarlcs. — This species is known only by the type and a few fragmentary 
specimens. The tj^pe shows the interior of a right valve. The ornamentation 
appears to be similar to the form from the Gault described above. On the dorsal 
half of the valve there are about 18 narrow ribs, which are crossed at regular 
intervals by concentric ridges, giving rise to a fimbriated appearance. About 8 
similar ribs are found on the dorsal part of the ventral half of the valve, below 
which are strongly curved growth-ridges. 

Typo. — In the Sedgwick Museum, Cambridge. 

Distribution. — Totternhoe Stone (zone of Hulastcv suhgluhusua) of Eurwell. 



Pinna decussata, GohJfnss, 18o7. Plate XIII, figs, -ia-c, 5, G. Plate XIV, fig. 1. 

1833. Pinna sulcata, <S'. WoodirariL Geol. Norfolk, p. 4:7, pi. v, fij,'. 23. 

1837. — DECUSSATA, A. Goldfusn. Petref. Germ., vol. ii, p. 1(JG, lA. cxsviii, 

fi!,'S. 1, 2. 

— — coMPRESSA, Goldfuss. Ibid., p. 1(37, pi. cxxviii, fig. 4. 

"r 1840. — PYRAMiDALis, U. B. GeiiiUz. Cbar. d. Scbiebt. u. Petref. des sachs. 

Kreidegeb., pt. 2, p. 55, pi. x, fig. 1, 

— — coMPEESSA, Geinitz. Ibid, p. 55. 

1841. — FENESTRATA, F. A. Buiner. Die Vcrsteiu. d. uord-deutsch. Kreidegeb., 

p. 65, pi. viii, fig. 22. 

— — DECUSSATA, Bonier. ILiiJ., p. 65. 

1846. — PYRAMIDALIS, H. B. GeiuHz. Gruudr. d. Versleiu., p. 451. 



' I have not seen any specimen of Pinna ? crassa, Fittou, * Trans. Geol. Soc.,' ser. 2, vol. iv (1836). 
p. 130 ; Morris, ' Cat. Brit. Foss.,' p. 180. 



100 CRETACEOUS LAMELLIBRAXCHIA. 

1846. Pinna decussata, A. E. Reuss. Die Versteiu. dor bohui. Kreidcforuiat., 

pt. 2, p. 14, pi. xxxvii, figs. 1, 2. 
1850. — — A. (VOrhigny. Prodr. tie Pal, vol. ii, p. 165. 

— — FENESTEATA, (V Ofbiytiij. Ibid., p. 246. 

— — DECUSSATA, J. de C. Sowerhy, in F. Diron. Geol. Sussex, p. 355 (p. 

386, ed. 2), pi. xxviii. 
fig. 20. 

— — DiLuviANA, H. B. Geinitz. Das Quadersandst. oder Kreidegeb. iu 

Deutsclilaud, p. 166. 

— — FENESTKATA, Gciiiitz. Ibid., p. 166. 

1854. — DECUSSATA, /. Morfis. Cat. Brit. Foss., ed. 2, p. 180. 

— — SULCATA, Morris. Ibid., p. 180. 

1873. — DECUSSATA, H. B. Geinitz. Das Elbthalgeb. in Sachseu (Palipouto- 

grapliica, vol. xx), pt. i, p. 211, pi. xlvii, 
figs. 4, 5 ; pt. ii, p. 53, pi. xv, figs. 2, 3 ; 
pi. xvi, fig. 1. 
1877. — — A. Fritsch. Stud, ini Gebiete der bolim. Kreideforiiiat., 

ii. Weisseuburg. u. Maluitz. Scliicht., p. 
120, fig. 86. 
1883. — — Fritsch. Ibid., iii. Iserscbicht., p. 104. 

1888. — — G. Mailer. MoUusk. d. uutersen. v. Biauuscliwoig (Jalirb. 

d. k. preussisch. geol. Landesanst. fiir 1887), 
p. 420. 

1889. — — Fritsch. Stud, im Gebiete dor bohm. Kreidoformat., 

iv. Teplitz. Scbicht., p. 79. 
? 1890. — — M. Blanchenhorn. Beitr. z. Geol. Syi'iens : Kreidesjst. 

in Mittel u. Nord-Svrion. p. 80. 
1893. — — Fritsch. Stud, ini Gebiete der biihm. Kreideforinat., 

V. Priesen. Scliicht., p. 94. 
1897. — -_ _ Ibid., vi. Chloinok. Sdiicht., p. 57. 

? 1894. — cf. DECUSSATA, A. Henniij. Oui Ahussandst. (Geol. Foreu. i Stook- 

holm Forhandl., vol. xvi), p. 522. 
1902. — DECUSSATA, J. P. J. Eavn. Mollusk. i Danmarks Kridtaflej., i. 

Lainellibr., p. 104. 

Non 1846. — — E. Forbes. Trans. Geol. Soc, ser. 2, vol. vii, p. 1.53 

(= P. arata, Forbes). 

Description. — Shell moderately elongate, triangular, laterally compressed, 
section rhombic, but becoming lenticular in the later portion. Dorsal margin 
straight, ventral margin slightly curved. 

Each valve is divided into two nearly equal parts. The dorsal part is flattened 
and bears from 7 to 9 strong rounded ribs, separated l)y broad, shallow, 
rounded depressions. The distance between the ribs increases in passing from the 
apex to the posterior extremity. In well-preserved specimens linear ridges are 
seen crossing the ril)s and interspiices at regular intervals. The dorsal portion of 



PINNA. 101 

the ventral pai't of the valve bears from 5 to 7 ribs similar to those on tlie 
dorsal part and of nearly uniform size, with transverse linear i-idges. On the 
ventral portion of the ventral part of the valve there are strong ridges or folds 
which form an acute angle with the last rib, and curve slightly towards the umbo. 
Measurements {approximate) : 

(1) (2) (3) 

Length . 125 . 117 . 120 mm. 
Height . 6G . 69 . OG „ 

(1) Chalk Marl, Folkestone. 

(2) Chalk, Newtimber (Sussex). 

(3) Cbalk, Trimingham. 

Bemarlis. — Most of the specimens of Pinna from the Chalk are very imperfectly 
preserved, and it is not unlikely that Ijctter material would show that more than 
one species could be distinguished. 

In the examples from Trimingham the ribs are rather broader and more 
rounded than in most of the specimens found at lower horizons. 

Ajfinltics. — This species is less elongate than P. crctacea (Schlotlieim),' and 
has the ridges on the ventral part of the valves more distinctly curved than in 
that form. It has a larger apical angle than P. Rohinaldina (see p. 0(3) ; also the 
shell is rather more compressed, and the ribs on the ventral part do not decrease 
regulai'ly in size as they do in P. Buhinaldina. 

P. sulcata. Woodward (Plate XIV, fig. 1), from the Norwich Chalk, as was 
suggested by J. de C. Sowei'by, does not differ from P. ilccussahi. AVooilwnrd's 
name is prior to tliat of Goldfuss, but since the original figure was scarcely 
sufficient for the recognition of the species and was not accompanied by any 
description, I do not think it is desirable that the well-knoAvn name P. decussata 
should be displaced by P. i^nlcata. 

Most of the English specimens of P. dccussata agree better with the figures 
given by Geinitz (1873) than with those of Goldfuss and Reuss. I5ut the example 
figured by Dixon seems to be very similar to the types of Goldfuss. 

Tyi)es. — From the Quadersandstone of Haltern (Westphalia) and Schandau 
(Saxony). The specimen figured by Dixon cannot be found. The type of P. 
sulcata is in the Norwich Museum. 

Distribution. — Chalk Marl of Ventnor and Folkestone. TerchratuHua zone of 
Arn Hill near Warminster. Zone of Holaster planus of Balsham, Chalk of New- 
timber. Zone oi Micro ster cor-amjuinnm of Charlton and Graveseud. Upper Chalk 
(zone of M. ror-tesUulinarinm or M. cor-anrjuinum) of Swaffham, Norfolk, (r) Zone 
of Acfinocama,!' qitadratus of Ea.st Harnham near Salisbury. Zone of Hrhmnitrlla 
mvcronata of Norwich. Chalk of Trimingham. 

1 Gciuita, 'Das Elbthalgeb.,' pt. li (1873), p. 54, pi. siv. tii,'s. -2, 3. 



102 CRETACEOUS LAMELLIBRAXCHIA. 



i'V(/«i7//— ASTARTID^, Gnnj. 
Genus — Astaete, J. Soicerbij, 1816. 

(' Min. Conch.,' vol. ii, p. 85.) 

Astaete elono.vja, iVOrhujiKj, 1844. Plate XIV, figs. 2 a, ft, 3. 

18-i2. AsTAKTE OBLONGATA, Dfslwijef ill A. Leijmerie. Mem. See. gc'ol. de France, 

ser. 2, vol. v, pp. 5, 24, pi. vi, fig. 1 
(non oblonga, Sowerby, 1826). 
1844. — ELONGATA, A. i.V Orhujiiij . Pal. Franc. Terr. Cri't., vol. iii, p. 68, pi. 

cclxiii, figs. 8 — 11. 
1850. — — iVOrhujnii. Froclr. de Pal., vol. ii, p. 77. 

1855. — — G. Cotteau. Moll. Foss. de I'Yonne, p. 69. 

1866. — — F. J. Pidet and G. Campiclu: Foss. Terr. Cn't. Ste. 

Croix (Maler. Pal. Suisse, ser. 
4), p. 310, pi. cxxiv, figs. 8, 9. 
1868. — — P. de Loriol. Valaugieu d'Arzier, p. 28, pi. ii, fig. 7. 

1871. — — F. Stoliczka. Palieout. ludica, Cret. Fauna S. India, 

vol. iii, p. 285. 
1000. — — A. WoUemanii . Die Biv. u. Gastrop. d. deutsch. u. liol- 

liind. Neocoms (Abhaudl. d. k. 
preussisch. geol. Land., N. F., pt. 
31), p. 102. 

Vcscviptluii. — Shell thick, elongate, rounded-oblong or oval, convex, compressed, 
very inequilateral. Postero-dorsal margin curving veutrally to join the obtuse 
and slightly curving posterior margin. Postero-ventral extremity rounded. Ven- 
tral margin nearly straight. Anterior margin rounded. Umbones small, with an 
indistinct keel passing from them towards the postero-ventral extremity. Luiiule 
narrow. 

Ornamentation consists of strong concentric ril)s, somewhat unequal in size, and 
separated by narrow grooves. Margins of valves creuulated. 

Length 21 mm. ; height 22 mm. 

Affinities. — Astarte cingvhifa, Geinitz,' from the Cenomaniau of Plauen, is 
probably identical with this species. 

A. cJoncjata is easily distinguished from other Cretaceous species by its elongate 
form. 

lieuiaii-.i. — The only specimens seen are in tlie Museum of Practical Geology. 

' 'Das Elbthalgeb. in Sacliseu' (Palasoulographica, vol. xx, pt. i, 1873), p. 226, pi. 1, fig. 8. Non 
A. cingulata, Coutejcau, 'Kimmerid. de Montbeliard ' (1859), p. 267, pi. xi, figs. 5 — 7. 



ASTARTE. 103 

One has the shell preserved, the others are internal casts showing deep muscular 
impressions. 

Tiipp.^. — Leymerie's specimens came from the Lower Xeocomian of Avalleur, 
Chenay, and MaroUes (Aube). D'Orbigny records specimens from the Lower 
Neocomian of St. Sauveur (Yonne). Pictet and Campiche figure specimens from 
the Valanginian of Ste. Croix. 

Distribution. — Lower Greensand of Seend. 



AsTARTE suiiACUTA, (VOrbigiiij, 1850. Plate XIV, figs. 4 — G. 

1844. AsTARTE CARiNATA, A. (TOvhHjmj. Pal. Fran9. Terr. Crot., vol. iii, p. fi3, 

pi. cclxii, figs. 1-3. {noTiA.carwata, 
Phillips, 1829.) 
1847. — ACTTTA, tVOrhigny. Ibid., p. 759. (non A. acuta, Eeuss, 1846.) 

1850. — suBACUTA, d'Orhiyny. Prodr. de Pal., vol. ii, p. 77. 

1866. — — F. J. Pictet and G. Campiche. Foss. Terr. Crct. Sle. 

Croix (Mater. Pal. Suisse, ser. 4), 

p. 318. 
1900 — — A. Wollemann. Die Biv. ii. Gastrop. d. deutsch. ii. 

hoUilnd. Neocoms (Abhandl. d. 

k. preussisch. geol. Land., N. F., 

pt. 31), p. 99. 

Description. — Shell triangular, much compressed, length greater than lieiglit, 
slightly inequilateral. Antero-dorsal margin long and concave. Postero-dorsal 
margin longer than the antero-dorsal, and either concave or nearly straight. Both 
of these margins form obtuse angles with the well-rounded margin of tlie ventral 
half of the shell. Umbones vei'y acute, projecting, often nearly median and not 
curved. Lunule narrow, with a sharp edge. Escutcheon ver}^ narrow. 

Ornamentation consists of prominent concentric ribs separated l)y l)road inter- 
spaces. The distance between the ribs increases in passing from the \uuho 
ventrally. Margins of valves crenulated. 
Measnreriicnts : 

(1) (2) 

Lenerth . 14 . 10 mm. 
Height . 11 . 8 „ 

(1, 2) Pt'i-Hrt-bed. East Sbalford. 

Affinities. — A. snhacuta is distinguished from the other Cretaceous species by 
its acute umbones and flattened valves. 

Ernvnis. — The only specimens which I have seen are in the ^Meyer Collection, 
Sedgwick Museum. 



104 CRETACEOUS LAMELLIBRANCHIA. 

Tijpe. — From the Neocoraian of Brienne (Aiilje). 

Distribution. — Perna-hed of East Slialford. Atlierfield Beds of Sevenoaks. 



AsTABTE siNUATA, iVOrtngnij, 1844. Plate XIV, figs. 7 — 9. 

1844. AsTAETE SINUATA, A. (VOrhigtiij. Pal. Fran9. Terr. Cn't., vol. iii, p. G9, pi. 

cclxiv, figs. 1 — 3. 
1850. — — (VOrliyny. Proclr. de Pal., vol. ii, p. 118. 

1856. — — F. J. Pktet and E. Renevier. Foss. Terr. Aptien (Mater. 

Pal. Suisse.ser. l),p. 89, 
pi. X, fig. 3. 
18GG. — — F. J. Pictet and G. Campiche. Foss. Terr. Crt't. Ste. 

Croix (Matur. Pal. 

Suisse, ser. 4), p. 311. 

1871. — — F. Stoliczka. Palocout. ludica, Cret. Fauua S. India, 

vol. iii, pp. 251, 285. 
1895. — — G. Maas. Zeitscbr. d. deutsch. geol. GeseUsch., vul. 

xlvii, p. 261. 
19U0. — — A. WoUemann. Die Biv. u. Gastrop. d. deiitsch. ii. 

lioUi'ind. Neoeoms (Abhaudl. d. k. 
preussisch. geol. Laud., N.F., pt. 31), 
p. 100. 

Deserijitiov. — Shell siib-quadi-ate, rounded ventrally, trniicated posterioi-ly, 
longer than high, slightly or moderately inequilateral, much compressed. A furrow 
extends from just behind the umbo to the sinuosity on the posterior margin, and 
cuts off a triangular, flattened, postero-dorsal part of the valve. Antero-dorsal 
margin nearly straight. Anterior margin rounded, passing gradually into the 
curved ventral margin. Posterior margin with a sinuosity above the postero- 
ventral ano^le. Postero-dorsal marg-in straiufht or slisfhtlv concave, lonsrer than the 
antero-dorsal margin, and forming an angle with the posterior margin. Umbones 
pointed, inconspicuous. Limule and escutcheon long, narrow, with sharp edges 
which have tooth-like ^projections where the ribs end. 

Ornamentation consists of rounded, concentric ribs separated by shallow 
furrows. The ribs are rather stronger on the posterior than on the anterior j)art 
of the shell, and are sinuoiis where they cross the posterior furrow. Smaller i'il)s 
arc present on the main ribs and furrows. 

Measurements : 









(1) 


(2) 


Length . 


. 




K) 


15 mm 


Heiglit . 


. 




14-5 . 


14 „ 


Tliickness 


. 




4- 






(1. 


2) 


Ci-ackeis, Atberfield. 





ASTARTE. 105 

Affimties. — A. miuata is distinguislied from other Cretaceous species of Astaiie 
by tlie furrow passing from the umbo to the posterior margin. Conrad' thought 
that this species might belong to his genus LirodiHciis. I am unal)le to express an 
opinion on this matter, since I have seen only three examples, none of which shows 
the hinge, nor is it seen in the figures given by previous writers. 

Type. — From the Aptian of Marolles (Aube). 

Distribution. — Lower Greeusand (Crackers) of Atherfield. Recorded by Pictet 
and Renevier from the Lower Greensand of Peasmarsh. 



AsTARTE UPWABENSis, sp. nov. Plate XIV, figs. lOa-r, l\a, b, 12. 

1883. AsTAETE, sp. uov., W. Keepimj. Foss., etc., Neoc. Upware aud Brickhill, 

p. 122, pi. vi. fig. 9. 

Description. — Shell ovate, a little higher than long, moderately and evenly 
inflated, moderately (or sometimes only slightly) inequilateral. Dorsal half narrow- 
ing gradually to the umbo ; ventral half larger and with evenly-rounded margin. 
Antero-dorsal border slightly concave ; postero-dorsal border long and convex. 
Umbones curving forward. Luuule large, ovate, depressed, with a sharp border. 
Escutcheon lanceolate, with a sharp edge. 

Ornamentation consists of many flattened, inconspicuous, concentric ribs 
separated by linear grooves. 



Measurements : 












(I) 


(^) (3) 


(4) 


(5) 


Length 


24 


21 . 19 


14 


lo mm. 


Height . 


25 


21-5 . 21 
(l-.'j) Lower Greensand, Upware. 


15 


14 „ 



Affinities. — This species presents some resemblance to -I. nflangiensi.'i, Pictet 
and Campiche,'- but its dorsal half is not so luirrow and pointed, and the antero- 
dorsal margin is less concave. It is also similar to A. liliodani, Pictet and 
Campiche,-' from the Gault of Gosne, but the umbones are less prominent. 

Astarfe npirar''nsis is distinguished from A. circiilaris, Gueranger,' by its ovate 
outline and greater height. 

T!/2)e. — Of the specimens of this species which were figured by W. Keeping as 

' ' Amer. Jouru. Couch.,' vol. v (186it), P- 46. 

- 'Terr. Crct. Ste. Croix ' (Mater. Pal. Suisse, ser. 4, 1866), p. 303. pi. cxxiii, figs. 3. 4. 

3 De Loriol, ' Gault de Cosne ' (1882), p. 94, pi. xii, figs. 1-7. 

* • Album Palt'ont. de la Sarthe * (1867), p. 12, pi. xv, fig. 12, pi. xvi, figs. 7. 8. 

14 



106 CRETACEOUS lAMELLIBRANCIIIA. 

Astarte, sp. nov., one is in the Sedgwick Museum (fig. 9(/), the other in Mr. J. F. 
Walker's collection (fig. \)h). 

Distrihiitioii.— Lower Greensancl of Upware. 



AsTARTE SENECTA, sp. uov. [ex Bean MS.] Plate XIV, figs. 18-20. 

1889. AsTARTE SENECTA [Bean MS.] fi. W. Lnmphnjh. Quart. .Jouni. Geol. Soc, 

vol. xlv, p. 616. 

Descriptiun. — Shell subtriangular, or approaching subquadrangular, .sometimes 
rounded, rather compressed, usually very inequilateral ; height usually a little 
greater than length. Anterior margin rounded, ventral margin curving slightly 
and often forming a rounded angle with the posterior margin, which is slightly 
curved and usually makes an obtuse angle with the postero-dorsal margin. 
Umbones small, curving forwards. Lnnnle ovate, dee]), Avith a .shai'p Ijorder. 
Escutcheon narrow, deep, with a sharp border. 

Ornamentation consists of strong concentric ribs, with sharp summits, separated 
by broad furro\\'s, on both of which are numerous small ribs. The ribs l)end 
sharply in passing on to the postero-dorsal part of the valve, and cut the postero- 
dorsal margin obliquely. Margins of valves strongly crenulated. 

Measurements : 

(1) (-') (3) W (5) (6) 
Lentrth . 23 22 21 19 13 20 



(7) (8) 


(9) 


(lU) 


(11) 


25 25 


23 


23 


-\ mm. 


22-5 22 


23 


22 


'^1 



Height . 21-5 20 19 17 11 24 

(1-5) Speotou Clay, Speeton. 
(6-11) Claxby Ironstone, Benuiworth Haven. 

Affinities. — Astarte veneris, Eichwald,' is similar to this species, but has a 
deeper and larger lunule, more ]irominent umbones, less compressed valves, and 
more slender ribs. Specimens of A. reiicris from the ' Volgian ' of Moscow are 
in Mr. Lamplugh's collection. 

Bemarks. — This species has been known to collectors for a long time, and lias 
appeared in lists of fossils under the name Asturte senecta, Bean MS., lint has not 
hitherto been described and figured. 

The s})ecimens from the Claxby Ironstone are, as a rule, more rounded in 
outline than those from Speeton, and their ornamentation is not so well preserved 
on account of the difficulty of separating the shells from the hard matrix in which 
they are found. 

' D'Orbiguy, in Murcliisou, de Verueuil, and de Keyserling, ' Gcol. Euss. d'Europe,' vol. ii (1845), 
p. 456, pi. xxxviii, figs. 21, 22. 



ASTARTE. 107 

Disfrihiifiou. — Zone of BelemniteH latemlU : in tlie Speoton Clay of Speeton 
and tlie Claxby Ironstone of Bonniworth Haven. 



AsTARTE, sp. Plate XIV, fig-. 2 1 . 

Bescrijdion. — Shell oval, moderately convex, slightly inequilateral, length 
greater than height. Antero-dorsal margin concave. Anterior margin rounded, 
passing gradually into the curved ventral margin. Postero-dorsal margin convex, 
forming a rounded angle with the posterior margin. Umbo pointed. 

Ornamentation consists of about 15 strong, rounded, concentric ribs separated 
by rounded furrows of greater breadth. Fine concentric ridges occur on both ribs 
and furrows. The ribs cut the postero-dorsal margin at a large angle ; they are 
more widely separated on the dorsal than on the ventral half of the valve. 

Length 12'5 mm.; height, 112 mm. 

Bemaiis. — This species is known by a single right valve only. The ornamenta- 
tion is somewhat .similar to that of A. senedd, but the slifll is more oval and less 
inequilateral, also the ribs are more numerous and form a largei- angle with the 
postero-dorsal margin . 

Distribtttio)i. — )Speeton Clay of Speeton. 



ASTARTE C.VNTABRIGIENSIS, Sp. UOV. Plate XIV, figS. 22(1, h, 23 rt, h, 24. 

1883. AsTARTE suBDENTATA, W. Keeping. Poss., etc., Neoc. Upware and Brick- 
hill, p. 122, pi. vi, 6^. 11 {non 
Eonier) . 

Descnption. — Shell subquadrate, longer than high, very inequilateral, moderately 
inflated, with the greatest convexity between the umbo and the postero-ventral 
angle. Postero-dorsal margin long, slightly convex, forming an obtuse angle with 
the truncated posterior margin, and a blunt angle where it joins the slightly convex 
ventral margin. Anterior margin rounded. Lunula deep, ovate, distinctly limited. 
Escutcheon deep, with a sharp edge. 

Ornamentation consists of strong concentric ribs bearing finer ribs. 

Measurements : 

(1) (2) (3) (4) (5) 

Length . 17-5 15 15 14 14 

Height . K? l:V.-. 13 12-5 12 

(1-8) Lower Greensand, Upwaro. 



(15) 


(7) 


(8) 


13-5 


13 


12 mm 


12-5 


11-5 


lOo „ 



108 CRKTACEOUS l.AMELLIBRANCHIA. 

Abilities. — This species was identified by W. Keeping with A. suhdentata, 
Romer,' from the Neocomian of Brunswick. 1 have submitted photographs of 
the British fossil to Dr. A. Wollemann and he agrees with me in thinking that it 
is quite distinct from A. snhdenlata. In the latter the shell is smaller, the valves are 
much flatter and more elongate, and tlic umbones are more pointed and less 
anterior in ])Osition. 

The ornamentation, when avoII preserved, is somewhat similar to that of A. 
seneda (see above), l)ut the shell is more inequilateral, more nearly quadrate in 
outline, and the postero-dorsal part is more compressed. 

Bemarl-s. — The ornamentation is often imperfectly preserved, and in some cases 
it has almost entirely disappeared. The hinge has not been seen. 

Tijpe. — The specimen figured by Keeping is in the Sedgwick Museum, Cam- 
bridge. 

Distnhutiou. — Lower Greensand of Upware. 



AsTAUTE cLAXBiENsis, sp. nov. Plate XIV, figs. 25-28. 

Description. — Shell small, thick, oval, longer than high, inflated, slightly inequi- 
lateral. Antero-dorsal margin concave, postero-dorsal slightly convex. Anterior 
margin well rounded. Ventral and posterior margins forming a regular curve. 
Umbones prominent, close together, nearly median, curved greatly inwards and 
slightly forwards. Lunule large, ovate, with sharp edges. Escutcheon lanceolate, 
smooth, distinctly limited. 

Ornamentation consists of strong, narrow, concentric ribs, separated by broad, 
deep furrows. Left valve with two stout cardinal teeth and a tooth at the niai'gin 
of the lunule. Margins of valves coarsely crenulate. 

Measnremrxts : 

(1) (2) (3) (4) (5) 

Length . 12 . 11 . 10 . 9 . 8 mm. 

Height . 10-5 . 10 . 9 . 8*25 . 7 „ 

(1-3, 5) Claxby Ironstone, Benuiworth Haven. 
(4) Spilsby Sandstone, Spilsby. 

Affinities. — Astarte claxbiensis shows considerable resemblance to certain species 
found in the Jurassic rocks ; thus Astarte robusta, Lycett,^ from the Cornbrash, seems 
to dilfer only in having the valves more elongate and the umbonal parts narrower. 

' ' Verstein. uorddeutscb. Ivieidegeb.' (1841), p. 71, pi. ix, fig. 9. Wollemann, ' Die Bivalvcn u. 
Gasterop. d. dcutsch. u. holliind. Neocoms ' (1900), p. 98, pi. v, fig. 2. 
" ' Suppl. Men. Mollusca Great Ool.,' etc. (1863), p. 74, pi. xxxv, fig. 6. 



ASTARTE. 109 

A. cordata, Trautscliokl/ is another example of the same type. A. Saiivagei, de 
Loriol,' from the Sequauiaii, i.s also similar to A, claxbienain, but appears to be less 
elongate. 

Diiifrihutioii. — Spilsby Sandstone (zone of Beh'mnitcs Inleraliti) of Spilsl:)y. 
Claxby Ironstone (zone of B. hitcrnHx) of Bcnniworth Haven. 



AsTARTE siJBCOSTATA, d'Ovhigny, 1850. Plate XIV, figs. 29-36. 

1842. AsTARTE LATicosTA, DcsJiaycs. In A. Leymerie, Mvm. Soe. geol. de France, 

ser. 2, vol. v, \>. 4, pi. iv, figs. 4, 5 
(uon A. laticosta, Deshayes, 1839). 

1844. — STRiATO-cosTATA, A. (VOrbigny. Pal. Frau9. Terr. Crct., vol. iii, 

J). 64, 1)1. cclxii, figs. 7-9 
(non A. striato-costata, Edmer, 
1836). 

1845. Venus (?) [steiato-costata], E. Forbes. Quart. Journ. Geol. See, vol. i, 

p. 241. 
1850. AsTAETE SUBCOSTATA, cVOrbigmj. Prodr. de Pal., vol. ii, \k 77. 

1854. — STEIATO-COSTATA, /. Morris. Cat. Brit. Foss., ed. 2, ]>. 187. 

1855. — SUBCOSTATA, G. Cotteau. Moll. Foss. de I'Yonne, p. 70. 

1856. — LATICOSTA, F. J. Pidet and E. Benevier. Foss. Terr. Aptien 

(Mater. Pal. Suisse, ser. 1), p. 88, 
pl. X, fig. 2. 
1865. — Leymeeii, K. A. Zlttd. Die,Bivalv. d. Gosaugeb. (Denkschr. d. k. 

Akad. Wien, Math.-nat. Classe, vol. 
xxiv), p. 156. 

1865. — LATICOSTA, H. Coquand. Mon. Ajitien de I'Espagne, p. 126. 

1866. — SUBCOSTATA, F. J. Pidet and G. Campiche. Foss. Terr. Cret. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), p. 307. 
? 1868. — STRIATO-COSTATA, E. Eicliwald. Letbtea Rossica, vol. li, p. 624. 
? 1868. — LATICOSTA, Ekhwald. Ibid., p. 628. 

p 1900. — Leymeeii, G. Mailer. Deutsch-Ost-Afrika, vol. vii, p. 552, 

pl. xxii, figs. 4, 5. 
1905. _ SUBCOSTATA, E. Harbort. Die Fauna der Scbauniberg-Lippe'schen 

Kreidemulde, p. 60, pl. iv, fig. 6. 

De>icription.—^\\e]\ small, usually rather convex, subquadrate or subtriangular, 
moderately or very inequilateral. Antero-dorsal margin concave. Anterior and 
ventral margins rounded. Postero-dorsal margin long, nearly straight, forming an 

1 C. Rouillier, ' Bull. Soc. Nat. Moscou,' vol. xix, pt. 2 (1846), pl. d, fig. 15 ; pl. e, fig. 1 ; vol. xxi, 
pt. 1 (1848), pp. 274, 275. Trautschold, Ibid., vol. xxxiii (1860), p. 347. 

2 De Loriol and Pellat, ' Mon. Pak'ont. ct Geol. etages sup. Jurass. de Boulogne-sur-Mer' (1874). 
p. 96, pl. sv, figs. 33, 34. 



110 CRETACEOUS LAMELLIBRANCHIA. 

angle ■\vitli the posterior margin, which is more or less truncated. Umbones 
inconspicuous. Lunule smooth, ovate, rather broad, with a sharp edge. Escutcheon 
smooth, deep, long. 

Ornamentation consists of 7 to 9 sharp, prominent, concentric ribs, with steep 
dorsal and gentle ventral slopes. Interspaces l)road. Between the ribs there are 
three or four very small concentric ribs and numerous fine radial strife. 

Measurements .- 

Length 
Height 



(1) 


(2) (3) 


(4) 


7 


6 . 5-5 


5 mm. 


5 


5 . 4-5 


4-5 „ 


(1) 


Atberfield Beds, Sevenoaks. 




(2) 


Atherfield Beds, Peasinarsh. 




(3,4) 


Per7ia-hed, East Shalford. 





Affinities. — This species resembles Astarfe frnnosa (see p. 112) Ijut is larger, 
less triangular in outline, with a larger apical angle and fewer ribs. yl. si)nilis, 
Goldfuss,' belongs to the same group, l)ut is more rounded in outline, and has more 
numerous ribs than A. siiljcostata. 

Forbes states that English examples of this species were identified by d'Orbigny 
as /]. nnmisvialix, d'Orbigny,- but adds that they resemble much more nearly 
d'Orbigny's A. striato-costata. They differ from the figures oi A. numismalis given 
by d'Orbigny in being less triangular, and in having the posterior end more 
truncated ; also the ribs are less numerous but more prominent, and form a larger 
angle with the postero-dorsal margin. English examples were also seen by Pictet and 
Renevier, and were identified by them with Astarte laticosta, Deshaycs (= striato- 
costata and suhcnntata, d'Orbigny). The specimen figured by d'Orbigny is more 
elongate than most of the English examples, but agrees in this respect with some 
found in the Atherfield Clay of Sevenoaks. The specimens figured by Leymerie 
are much larger than the English examples, and the ribs are more numerous and 
less prominent. Some of the differences seen in the figures of the authors quoted in 
the synonymy are probably due to the differences in the age of the specimens. In 
the young specimens the posterior end is more rounded, in old specimens it is 
more truncated. 

Bemarl-s. — Specimens which occur in the Crackers of Atherfield (Plate XV, figs. 
1 , 2) differ slightly from those described above, but probably constitute only a local 
variety ; the valves are not quite so convex, the ribs are rather more numerous and 

' Tor figures and references see Holzapfel, ' Die Mollusk. Aachen. Kreide ' (Palaeontographica, vol. 
XXXV, 1889), p. 194, pi. xix, figs. 11—15. A. similis was referred to the genus Gouldiahy Stoliczka : 
Holzapfel discusses this subject, and I am in agreement with his conclusions. 

- ' Pal. Pran9. Terr. Crut,,' vol. iii (1844), p. 03, pi. cclxii, figs. 4—0; Pictet and Campichc, 'Terr. 
Crct. Ste. Croix' (1800), p. 309. 



ASTARTE. ] ] 1 

less prominent, and the posterior end of tlie shell is rather moiv pointed. This 
form resembles A. (nu/iihtln, (Jueranger.' 

Ti/pes.— The types of .1. laticosi,, came from the Neocomian of Ohaoui-ce and 
Jully (Aube). D'Orbigny's specimens of A. striato-costata were obtained from the 
Neocomian of Marolles (Aube), Attanconrt (Hante-Marne), and Saint-Sanvenr 
(Yonne). The specimens described by Forbes are in the Mnsenm of the Geological 
Society (No. 2181). 

DUnbution.—AthevRcld Beds of Peasmarsh and Sevenoaks. J'eniM-hcd of East 
Shalford, and probably Atherfield. Recorded by Topley from the Atherfield Beds 
of Haslemere, and the Hythe Beds of Lympue. 



AsTARTE, sp. Plate XV, figs. 3, 4. 

Some specimens from the Folkestone Beds of Folkestone are very similar 
to J. suhcostata, d'Orbigny, but are lai'ger, less elongate, and have a smaller 
apical angle. 



AsTAUTK Omaijoidks, sp. nov. [ex flunh/cr MS.]. Plate XV, figs. 5-7. 

DpscripHon. — Shell small, triangular or sul>quadrate, compressed, slightly 
inequilateral, height and length nearly equal. Dorsal half of valves pointed. 
Antero-dorsal margin slightly concave; postero-dorsal margin rather longer and 
nearly straight, the remaining margin forming a regular curve. Umbones pointed. 
Margins of valves finely crenulate. 

Ornamentation consists of a few (usually 6 or 7) prominent, sharp, concentric 
ribs, with steep dorsal slopes and more gentle ventral slopes. Interspaces vci'v 
broad. The ribs become more distant from one another in passing from the uniljo 
to the ventral margin. A few very faint concentric ribs are sometimes present also. 

Measurements ; 

(1) (2) (3) 

Length . 5-0 . 4-25 . 4-0 mm. 

Height . 4-75 . 4-25 . 4-0 „ 

(1—3) Gault, Folkestone. 

AlJhiities. — This species is closely allied to A. sithcoatiitii. (see j). lO'.t), but is 
relatively shorter and less convex, and has a smaller ai)ical angle and rather fewer 
ribs. 

1 'Album I'ali'out. Jo la Sarthc ' (.1«(37), p. 13, pi. xvi, ii^f. 5. 



112 CRETACEOUS LAMELLIBRANCHIA. 

Remarls. — Hince the name Omalioides has been used in stratigraphical lists, ^ it 
seems desirable to retain it, although its construction is not in accordance with the 
recommendations of the International Congress of Zoology. 

Distribution. — Gault (zones vii, x, and xi) of Folkestone. 



AsTABTE FOKMOSA, Soivevhi/, 183G. Plate XV, figs. 8-13. 

18-36. AsTARTE FORMOSA, /. de C. Sowerhy. Traus. Geol. Soc, ser. 2, vol. iv., pp. 

2.39, 341, pi. xvi, fig. 16. 
1842. — — F. Bomer. De Astartarum Genere, p. 21. 

1850. — —A. d'OrhHjny. Prodr. de Pal., vol. ii, p. 160. 

1854. — —J. Morris. Cat. Brit. Foss., ed. 2, p. 186. 

1871. — — F. Sfoliczka. Palaeont. Indica, Cret. Fauna S. India, vol. 

iii, p. 285 (:'' Gouldia). 

Nou 1842. — — H. B. Geiiiitz. Char. d. Scbicht. u. Petref. des sachs.- 

bohm. Kreidegeb., pt. 3, p. 7G, pi. x.\i, 
fig. 19 (see Geinitz, Elbthalgeb. i, i>. 
227). 
— 1844. — —A. d'Orhi(jnij. Pal. Franf. Terr. Cre't., vol. iii, p. 65, j.l. 

cclxii, figs. 10 — 12 {A. siihformusa, 
d'Orb., 1850). 

Description . — Shell small, rather convex, sub-triangular, moderately inequilateral. 
Antero-dorsal margin slightly concave. Anterior and ventral margins forming a 
regular curve. Posterior margin less curved, often truncated, and forming an 
obtuse angle with the long and slightly convex postero-dorsal margin. Uml^ones 
pointed. Lunule large, ovate, depressed, smooth, with a sharp border. Escutcheon 
long, lanceolate, depressed, smooth, with a sharp border. Margins of valves smooth. 

Ornamentation consists of strong concentric ribs with sharp summits, separated 
l)y broad concave interspaces. The rilxs end abi'uptly at the margins of the linuilf 
and escutcheon. On the riljs and interspaces fine concentric ridges may be seen. 

Measurements : 

(1) (2) (3) (4) 

Length . 5-0 . 475 . 4-5 . 4-0 
Height . 4-5 . 4-5 . 4-0 . 3-75 

(1 — 6) Blackdown. 

Affinities. — A.furniosu is smaller and has more numerous ribs than A. suhfurnwsa, 
1 Price, ' The Gault ' (1879), p. 58 ; Jukes-Browne, ' Cret. Eocks of Britain,' vol. i (1900), p. 465. 



(5) 

3-2.5 


(0) 

. 3-0 mm 


3-0 


, 2-5 „ 



ASTARTE. 113 

d'Orbigny.^ J. acuta, Reuss,- is another allied form, Ijut possesses fewer ribs than 
A. formosa. See also A. suhcostata (p. 109). 

Ti/pe. — From Blackdown, in the Bristol Museum. 

Disfribatio)i. — Upper Greensand (zone of Schlocnhaclila rodraia) of Blackdown 
and Haldon. 



AsTAETE IMPOLITA, Soiccvhij, I80G. Plate XV, fig. 1-1. 

1836. AsTARTE IMPOLITA, /. cle C. Sowerhij. Trans. Gool. Soc, ser. 2, vol. iv, 

pp. 239, 341, pi. xvi, fig. 18. 
1854. — — /. Morris. Cat. Brit. Foss., ed. 2, p. 187. 

The only example of this which I have seen is the type specimen from the 
Greensand of Blackdown.^ Both valves are present, but the parts near the umbo 
and lunula are missing. The specimen is in the Bristol Museum. 



Sub-genus — Eriphyla, W. M. Gabh, 1864. 

(' Geol. Surv. California, Palscout.,' vol. i, p. 18U. Stoliczka, ' Palajout. ludica, Cret. Fauua, S. India,' 

vol. iii, 1870, p. 156.) 

AsTARTE (Eriphyla) obovata, Sunrrbi/, 1822. Plate XV, figs. 15-18. I'late XVI, 

figs. 1-3. 

1822. AsTARTE OBOVATA, /. (le C. Soiverby. Min. Couch., vol. iv, p. 73, pi. cccliii. 

1842. — — F. Rimer. De Astartaruin Genere, p. 22. 

184.0. — — E. Forbes. Quart. Journ. Gool. Soc, vol. i, p. 241. 

1850. CoKBis OBOVATA, ^1. (VOrhignij. Prodr. de Pal., vol. ii, p. 78. 

1852. AsTARTE Bkunneei, F. J. Piciet and W. Rotu. Moll. Foss. Grts verts de 

Geneve, p. 435, pi. xxxii, fig. 3. 
— — GURGiTis, Piciet and Roux. lljid., p. 436, pi. xxxiii, fig. 1. 

1854. — OBOVATA, J. Morris. Cat. Brit. Foss., ed. 2, p. 187. 

1857. — — F.J.PictetamlE.Eeiievier. Foss. Terr. Aptieu (Miitt'r. 

Pal. Suisse, ser. 1), p. 86, pi. xi, fig. 1. 



> ' Prodr. de Pal.,' vol. ii (1850), p. 77. 

= ' Die Versteiu. der bolini. Kreideionnat.,' pt. 2 (1846). [>. 3, pi. xxxiii. fig. 17; ]<]. xxxvii, fig. 14; 
NGtling, 'Die Fauna d. baltisch. Cenomau.' (Paloeont. Abhandl., vol. ii, 1885), p. 28. \<\. v, fig. 1. 
According to Niitliiig, A. jilauoisis, Geiuitz, is a svnouyni of A. acuta. 

' Astarle miiltistriata was also described bv J. de C. Sowerbv from Blackdowu, but I liave not 
seen any example of it. See 'Trans. Geol. Soc.,' ser. 2, vol. iv. ]ip. '240, 341, I'l. xvi, fig. 17 ; Morns, 
'Cat. Brit. Foss.,' ed. 2 (1854), p. 187. 

1.') 



114 CRETACEOUS LAMELLIBRANCHIA. 

? I860. AsTiRTE OBOVATA, H. Coqiiand. Mou. Aptieu de rEspague, p. I'l'l. 

pi. xiii, figs. 3, 4. 
1866. — — F. J. Pidct and G. Campiclie. Foss. Terr. Crct. Ste. 

Croix (Mater. Pal. Suisse, sur. 4), p. 312. 
1871. — — (Ebyphyla), 2*'. /S<oZic«A;a. PaliBont.Indica.Cret.Fauua. 

S. ludia, vol. iii, p. *285. 
1892. — — 0. Buhrciidscn. Zeitscbr. d. deutsch. geol. Gesellsch., 

vol. xliv, p. 22. 

Description. — Shell large, oval, transverse, moderately inflated, very ineciui- 
latcral. Anterior margin rounded, concave in front of the nmbo. Behind the 
umbo the dor.sal margin has a gentle and regular curve. Posterior margin roumled 
or sub -truncate. ITmbones prominent, curving forward. Lunule deep. Escutcheon 
narrow, deep. 

Ornamentation consists of numerous, strong, close, somewhat irregular concent i-ic 
ribs, on which fine, concentric, linear ribs occur. 

Measurements : 

(1) (2) (3) (1) (0) (6) 

Length . . 75 . 74 . 73 . 70 . 72 . 71 mm. 
Height . . 62 . 58 . CO . 59 . 63 . 59 „ 

(1-4) Per«n-bed, Atlierfield. 
(5, 6) Per»a-bed, Sandown. 

Affinities. — Astarte Beaumonti, Leymerie,' and A. transversa, Leymerie,- are 
closely allied to A. ohovata, and were regarded by Forbes as merely varieties of the 
latter. Pictet and Renevier (1857) were inclined to regard the differences as not 
of specific importance. Pictet and Campiche (1866), however, kept the three forms 
distinct, but wei^e uncertain whether they should be regarded as species or varieties. 
They state that in A. Beaumontl the margin is smooth, Avhilst in A. obooata and 
A. transversa it is crenulated. In the first two forms the posterior margin i.s nioi-e 
rounded, Ijut in the last it is more truncate. It is very doubtful whether the 
crenulation of the margin is a feature of specific importance in Astarte; indeed, 
one writer^ thinks that it is a characteristic of sex. Whether the other differences 
are of specific value can be determined only by the comparison of a number of 
examples of A. Beaumunti and A. transversa with specimens of A. ohovata. 

1 ' Mem. Soc. geol. de France,' vol. v (1842), pp. 4, 24, pi. iv. fig. 1. D'Orbigny, 'Terr. Cret.,' 
vol. iii (1844), p. 60, pi. eclx. Pictet and Campiche, 'Terr. Cre't. Ste. Croix' (1866), p. 300, pi. cxxiv, 
fig. 1. WoUemaun, ' Biv. u. Gastrop. d. deutsch «. hoUiiud. Neocoms ' (1900), p. 95. 

'■^ Op. cit. (1842), pp. 4, 24, pi. v, fig. 5 D'Orbigny, "p. cit., p. 61, pi. cclxi. Pictet and C.impiche, 
op. cit., p. 301, pi. exxiv, fig. 2. De Loriol, ' Auim. Invert. Foss. Mt. Salcve ' (1861), p. 68, 
pi. viii, fig. 9. 

■' A. Ostrooumoff, 'Zool. Anzeiger,' vol. xxiii (1900), p. 499. 



ASTARTE. 115 

The shallow pallial sinus shown in internal casts, and the characters of the hinge 
seem to warrant the reference of this species to the sub-genus Eriphyla. 

Remarl-fi. — Some of the specimens found in the Isle of Wight have the posterior 
end rounded, but in the larger number it is more or less distinctly truncated. The 
former approach A. Bcaumovii ; the latter resemble A. transversa. 1 liave not seen 
any examples from the Isle of Wight which show the internal margin of the valve 
sufficiently clearly to determine whether it is crenulate or not, but in an internal 
cast from the Hythe Beds of Hythe (Museum of the Geological Society, No. 2187) 
tlie crenulation is distinct. 

The specimens of A. ohucata show a fairly large amount of variation. In some 
the anterior part of the valve is quite short, as in Leymerie's figure of .1. irniis- 
versa; in others it is much longer. The relative height and length, the amount 
of rounding or truncation of the posterior margin, and the coarseness of the 
ornamentation also vary. 

The specimens from the Hythe Beds of Hythe are very poorly preserved. 
Those from the Greensand of Blackdown and Haldon appear, so far as one can tell 
from the few perfect specimens available, to be rather shorter than most of the 
Lower Greensand examples. 

Types. — The type cannot be found ; it came from the Peyna-bed of Sandown. 

Distnhution. — Lower Greensand {Perna-hed) of Atherfield and Sandown. 
Recorded by Topley from the Atherfield Beds of Peasemarsh and Shalford, and 
from the Hythe Beds of Hythe and Lympne. 

Upper Greensand (zone of Schkv.nhacJda rust rata) of Blackdown and llaldon. 



AsTAR'i'E (Eripiiyla) l^vis {Phillips), 1829. Plate XVI, figs. 6-7. Plate XVII, 

fig. 1. 

1829. Crassina l«vis, J. Phillips. Gcol. Yorks., p. 122, pi. ii, fig. 19 {V fig. 18). 
1835. AsTARTE LiEvis, Phillips. Il.i.l., c.l. 2, pt. 1, p. 158 (ed. 3, 1879, p. 252). 
1854. — — /. Morris. Cat. Brit. Foss., ed. 2, p. 187. 

Description.— fiheW large, thick, convex, ovate, usually considerably inequilateral; 
height and length nearly equal, or the height may be rather greater than the length 
or vice veisd. Antero-dorsal margin rather long and slightly concave; postero- 
dorsal margin very long and moderately convex. Anterior and ventral margins 
well rounded. Posterior extremity rounded or sometimes subangular. Urabones 
large. Lunule large, ovate, deep, nearly smooth, with a sharp border. Escutcheon 
narrow, deep. 



lie. CRETACEOUS LAMELLIBRANCHIA. 

Ornamentation consists of numerous, rather strong, narrow, concentric ribs 
■which are somewhat irregular. 

Hinge-plate broad, triangular. In the left valve two strong cardinal teeth and 
one lateral at the margin of the lunule. Teeth of right valve not seen. Margins 
of valves strongly crenulate. 

MeasuremcnU : 

(1) (2) (3) (4) 

Length . 57 . 51 . 51 . 44 mm. 
Height . 59 . 56 . 47 . 39 „ 

(1-4) Claxhv Ironstone, Benniworth Haven. 

Affinities. — This species is allied to Jsfurte Salvia inii, de Loriol,' of which good 
specimens are found in the Portland Sands of Swindon. In some cases the resem- 
blance is very close, but generally the umbones are more prominent, the antero- 
dorsal margin relatively longer, and the valves more convex in A. la^ris than in 
A. Ssemaitni. 

A. Buchi, Romer,^ is apparently allied to A. IkvIk, liut is distinguished by the 
greater anterior curvature of its umbones. A. ijvjantea, Leymerie,^ is less inequi- 
lateral and more elongate than A. Iseds. 

Remarks. — Most of the examples of this species have been obtained from the 
Claxby Ironstone. Oidy two have been seen from the Speeton Clay, one being in 
the Leckenby Collection (Sedgwick Museum), the other in Mr. Lamplugh's Col- 
lection ; these appear to agree with the larger example of Asturfe la^vis figured by 
Phillips (fig. 19). 

Types. — The type, from the Speeton Clay, appears to be missing. 

Distribiition. — Claxby Ironstone (zone of Belemnites laternHs) of Benniworth 
Haven. Speeton Clay of Speeton. 



AsTARTE (Ekipiiyla) STRIATA, Sowcrby, 1826. Plate XVII, figs. 2-7. 

182G. AsTARTE STRIATA, /. lie C. Sowerby. Min. Conch., vol. vi., p. 36, \>\. dxx, 

fig. 1. 
1836. — CONCINNA, /. dt; C. Sowerhy. Trans. Geol. See, ser. 2, vol. iv, 

pp. 239, 341, pi. xvi, fig. 15. 
1842. — — F. Edmer. De Astartariun Generc, p. 21. 

1 De Loriol and Pellat, ' Portlandien de Boulogne- su r-mer ' (1866), p. 68, pi. vi, fig. 9. E. G. 
Skeat and V. Madsen, ' Jur. Neoe. and Gault Boulders in Denmark' (1898), p. 123, pi. iii, fig. 2. 

- ' De Astartarum Gonere ' (184-2). p. 20, fig. 4. Pictet and Rcnevier, ' Poss. Terr. Aplien' (1856), 
p. 85, pi. X, fig. 1. 

' For references see Pictet and Campiclie, ' Terr. Cret. Ste. Croix' (1866), p. 298. 



ASTARTE. 1 ] 7 

1850. AsTARTE STRIATA, A. d'Orhifjiuj. Prodr. de Pal., vol. ii, p. 160 (partim). 

— — CONCINNA, (VOrhigmj. Ibid., p. 160. 

1854. — STRIATA, /. Morris. Cat. Brit. Foss., ed. 2, p. 187. 

— — CONCINNA, Morris. Ibid., p. 186. 

1866. — STRIATA, F. J. Pictel and G. Campiche. Foss. TeiT. CrOt. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), p. 230. 
1871. — — (Eryphila), i^. iS'foHczi-a. Palseont. ludica, Cret. Fauna 

S. India, vol. iii, p. 285. 

— — CONCINNA (Eriphyla), Stoliczku. Ibid., p. 285. 

? 1873. Eriphyla striata, H. B. Oeinitz. Das Elbthalgeb. in Sachsen (Palseon- 

tographica, vol. xx, pt. 1), p. 228, 
pi. li, figs. 1-3. 

Description. — Shell with rounded outline, sometimes nearly orliicular, usually 
only moderately inequilateral, moderately convex. Length usuallj^ a little greater 
than height, but occasionally less. The margin in front of the umbo is concave 
for a short distance ; behind the umbo it is convex ; the anterior, the ventral, and 
posterior margins form a more or less regular curve. Umbones rather small, 
placed a little in front of the median line. Lunulc small, deep, with a sharp edge. 
Escutcheon narrow. 

Ornamentation consists of numerous small concentric ribs, wliicli are slightly 
irregular and are separated l^y linear grooves; at intervals somewhat deeper 
grooves may occur. 

Hinge-plate wide. Two cardinal teeth in each valve, and one lateral tooth 
next the lunule in the left valve. Adductor impressions deep, the anterior some- 
what elongated. Pallial sinus shallow, rounded. Margins of valves smooth. 

Measurements : 

(3) (4) (5) 

44 . 42 . 39 

41 . 43 . 37 

(1-8) Blackdown. 

Affiiiifies.~Th\s species is closely allied to A. (Eriphi/h) lenticularis (Goldfuss),' 
but the outline of the valve is less regularly orl)icular. 

Asfdiie Koniad-i, d'Archiac,- from the Tourtia of Touruay, was regarded by 
d'Orbigny, Pictet and Campiche, Stoliczka, and Geinitz as a synonym of A. striata. 
I have not seen any exam|)le of the former, but it appears to differ from .1. .•<triata 
in having less prominent umbones, more inflated valves, a more regularly orbicular 

1 'Petref. Germ.,' vol. ii (1840), p. 228, pi. cxlvi, fig. 16. Holzapfel, 'Zeitschr. d. doutsch. geol. 
Gesellscb.,' vol. xxxvi (1884), p. 458, pi. vi, figs. 1, 2, and ' Palseontographica,' vol. x.xxv (1889), 
p. 195, pi. xiv, figs. 5-7. 

« 'Mi'm. Soc. geol. de France,' ser 2, vol. ii (1847), p. 302, pi. xiv, fig. 4. 





(1) 


(2) 


Length . 


46 


. 45 


Height . 


45 , 


. 42 



(G) 


(7) 


(8) 


37 , 


. 35 . 


28 mm 


34 , 


. 34-5 . 


27-5 „ 



118 CRETACEOUS LAMELLIBRANCHIA. 

outline, and apparently also fewer ril)s. Two imperfect specimens from the 
Cenomanian (Bed 11) of Dunscombe were referred to A. Komnchi hy tlie late 
C. J. A. Meyer, but tliey are less convex than that species aiid seem to agree 
more nearly with A. xtriafa. 

Astarte concinna, Sowerby, was regarded by Stoliczka as probal)ly identical with 
A. striata. It is known by the type specimen only, and agrees with A. striata, 
except that it is rather higher and more inequilateral. I believe that it is merely 
an individual variation of A. striata. 

Types. — From Blackdown, in the British Museum. The type of A. concivna is 
from Blackdown and is now in the Bristol Museum. 

Distrihutioii. — Upper Greensand (zone of Sclihrnliacliin msfrata) of Blackdown. 



Genus— Oris, M. J. L. Defrance, 182-5. 
(' Diet. Sci. nat.' vol. xxxvi, p. 219.) 

Oi'is NEOCOMiENSis, d'Orhigny, 1844. Plate XVII, figs. 8-12. 

1842. Opis a. Leymerie. Mem. Soc. geol. dp France, ser. 2, vol. v, 

p. 25, pi. vii, fig. 4. 
1844. — NEOCOMIENSIS, A. cVOrlngny. Pal. Fran9. Terr. Crct., vol. iii, p. 51, 

pi. ccliii, figs. 1 — 5. 
1850. — — d'Orbigny. Prodr. de Pal., vol. ii, p. 76. 

1855. — — G. Coitcau. Moll. Foss. de IToune, p. 67. 

1857. — — F.J. Pictet and E. Renevicr. Foss. Terr. Aiptien{Mat6r. 

Pal. Suisse, ser. 1), p. 
83, pi. ix, fig. 7. 
1861. — Desoei, p. (le Lorinl. Anim. Invert. Foss. Mt. Saltve, p. 66, pi. viii, 

figs. 4—7. 
1866. — NEOCOMIENSIS, F. J. Pictet and G. Campiche. Foss. Terr. Crt't. Ste. 

Croix (Mator. Pal. Suisse, ser. 4), 
p. 324, pi. cxxv, figs 3, 4. 
1868. — — P. de Lorinl. Valangien d'Arzier, p. 31. 

9 1871. — — W. A. Ooster. Protozoa Helvet., vol. ii, p. 101, pi. xv, 

fig. 17. 
1883. — — W. Keeping. Foss. etc., Neoc. Upware and Brickhill, 

p. 121, pi. vi, fig. 8. 
1900. — — A. Wollemann. Die Eiv. u. Gastrop. d. clcutscli. u. 

liolliind. Neocoms (Ablumdl. d. k. 
preussisch. geol. Land., N. F., pt. 
31), p. 102. 

Description. — Shell trigonal or sub-quadrilateral, much higher than long, 
inequilateral, greatly inflated, but with flattened sides. Anterior margin rounded. 



OPIS. 119 

Posterior margin truncated, slightly concave, forming an angle with the gently 
curved ventral margin and also with the postero-dorsal margin. Umbones 
prominent, slender, greatly incurved, almost touching in the young, Ijut separated 
in older specimens. A prominent carina extends from the umbo to the postero- 
ventral angle, cutting off an area which is divided into two parts by a prominent 
but rounded carina which ends at the postero-dorsal angle ; the outer part only of 
the area is seen in a side view, and is concave ; the inner part is depressed, and its 
dorsal portion is flattened and resembles a lunule. Lunide very large, cordate, 
flattened. 

Ornamentation consists of many small concentric ril)s se])arated by narrow 
grooves. Behind and in fi'oiit of the flattened jiart of tlie valve this (irnaineiitatidii 
becomes less distinct or may disappear altogether. Margin of valve entire. 

Measurements : 

(1) (2) (3) (4) (5) 

Length . 23 . 22 . 20 . 14 . 14 mm. 

Height' . 35 . 33 . 29 . 20-5 . l'.» „ 

Thickness . 26 . 26 . 24 . 16 . 15 „ 
(1 — 5) Lower Greeusaucl, Upware. 

Affinities. — This species shows some resemblance to 0. Hnganliana, d'Orbigny,- 
from the Gault. 

Eemarlis. — The shell is relatively higher in large than in small specimens. In 
all the examples obtained from Upware the shell is preserved. Specimens irom 
Seeud are in the Museum of Practical Geology. 

Ti/jyes. — Leymerie's specimen came from the Lower Neocomian of Bernon 
(Aube). D'Orbigny's specimens were obtained fi'om Saint Sauveur (Yonue), 
Bernon, and Marolles. The specimen figured by Keeping is in the Sedgwick 
Museum. 

Dii^friliiition. — Lower Greensand of Upware and Seend. Internal casts, 
prolnil)ly belonging to this species, are found in the Lower Greensand of Colesliill 
near Faringdon. 



OpIS IIALDONEXSIS, sp. uov. Plate XVIII, fig. 1 ii-(J. 

DesrHjifion. — Shell trigonal, liigher tlian long, moilerately inenuilateral, convex, 
wilh flattened sides. Anterior margin slightly convex, passing gradually into the 

' Measured from tlie umbo to the postero-veutral angle. 

i Syn. 0. SahandUina, cVOrbiguy, 'Pal. Frau^. Terr. CrOt.,' vol. iii (1844). p. 53, pi. cclvii. figs. 
4-6 ; Pict«t auJ Roux, ' Moll. Foss. Grcs verts de Geneve' (1852), pp. 432— 434. pi. xxxii. tig. 1. 



120 CRETACEOUS LA.MEJ.LIBRAX('HIA. 

sliglitly curved ventral margin. Posterior margin somewhat oblique, slightly 
concave. Postero-ventral angle rounded. Umbones high, prominent, not much 
incurved. A jn'oiiiiuent, rounded carina extends from the umbo to the postero- 
ventral angle, and cuts off a posterior area which is divided into two parts by a 
sti'ong, rounded carina ending at the postcro-dorsal angle. The part of the area 
between the carinas is concave ; the part l^ehind the median carina is deeply 
depressed. Lunule large, very deep, flattened. Surface of shell apparently 
smooth. Length, 48 mm. Height, 58 mm. 

Affi7iities. — It is possible that this species may be related to 0. Gallicnnd, 
d'Orbigny,' which seems to be known by casts only, but tlie height of the shell 
appears to be relatively less. 0. Gallieiuiei has been identified by some authors 
with 0. hirorii!.'< (Geinitz) - f rom the Cenomanian of Plauen. The latter differs 
from the species described above in possessing strong concentric ribs and in the 
absence of a carina between the umbo and the postero-ventral angle. 

h'l'iniirks. — Tlie only undoubted example of this species which I have seen is a 
right valve collected by the late W. Vicary, and now in the British Museum. The 
surface of the shell is not well preserved, but appears to have been nearly smooth. 

An imperfect specimen of a large Opis (length about (33 mm.) from the 
Chloritic Marl of Eggerdon Hill (Dorset) is in the Sedgwick Museum, Cambridge, 
and may belong to this species. 

Distribtitioit. — Upper Greensand (zone of Schlfienhachhi rodnita) of Haldon. 



Oris, sp. PI. XVII, figs. 13 <i-c, 14 <i-c. 

Dcscrijitiui). — Shell small, sul)-triangular, rather oljlique ; greatest convexity 
along the carina. Antei'ior margin rounded; posterior margin slightly convex. 
Umbones prominent, sliarp, considerably curved anteriorly. Carina sliai'p, 
prominent, cutting off a steeply sloping posterior area, which is not divided by a 
median carina. Sides of sliell flattened, sloping slightly in front of the carina, and 
passing gradually into the anterior part of the shell. Lunule very deep, with a 
sharp border. 

Ornamentation consists of regular, concentric ribs. Postei-ior area nearly 
smooth. 

> • Vdl. Fniiu;. 'iViT. Civt.,' vol. iii (18-J-t), pi. CL-lvii///.s tii;. 5 (not tlesfnlH.'d iu the text); 
(ji lu'rauger, ' Alhuiii PaK'oiit. de la Sartlio ' (1867), p. 17, pi. xxii, fij,'. 13. 

2 "Das Elhthal^'el). iu Sachsen" (' Palicoiitographiea,' vol.xx. pt. 1, 1873), p. 227, pi. 1, fii^'s. 1—3. 
luterual casts of OjJis from the base of the Chalk at Maideu Newtoii aiul Chard have beeu recorded 
as 0. hiconm? (Gein.) by Jiikes-Browue, ' Cret. Eocks of Britain,' vol. ii (1903), pp. 113, 122. Two 
of the specimens on which the determiuation was based are in the Oxford Museum. 



CARDITA. 121 

Measurements : 

(1) (2) 

Length . . . 8 . 7"o iiiiii. 

Umbo to postero- ventral angle . 12 . ll'O „ 

(1, 2) Haldou. 

Affinities. — This species may perhaps be related to 0. cenomanensis, Gudranger/ 
but the figure of the latter is too indistinct for recognition. 

Bemarls. — There are four examples of this species in the Vicary Collection, 
British Museum. 

Distribution. — Upper Greensand (zone of Hrlilimhaclna rustniln) of Haldon. 



i^«m%— CARDITID^, Uill. 

Genus — Cahdita, ./. G. Bruguiere, 1792." 
(' Encyc. uii-th., Vers,' vol. i, p. 401.) 

CAiiDiTA? FENESTEATA (Forbes), 1845. Plate XVIII, figs. 2-4. 

1845. Ventjs ? FENESTEATA, E. Forbes. Quart. Jouru. Geol. Soc, vol. i, p. 240, 

pi. ii, fig. 6. 
1850. Cardita — A. d'Orbigny. Prodi-, de Pal., vol. ii, p. 77. 

1854. Venus — J. Morris. Cat. Brit. Foss., ed. 2, p. 230. 

1856. Caedita — F. J. Pidet and E. Renevier. Foss. Terr. Aptieu 

(Mater. Pal. Suisse, ser. 1), p. 82, 

pi. is, fig. 4. 
1866. — — F.J. Pidet and G. Campidie. Foss. Terr. Crt't. Stc. 

Croix (Mater. Pal. Suisse, ser. 4), 

p. 333. 
1871. — — F. Stoliczlta. Palseont. Indica, Cret. Faima S. India, 

vol. iii, p. 287. 

Description. — Shell oval or somewhat rhomboidal, much longer than high, very 
inequilateral, moderately inflated, but with flattened sides. Anterior margin 
rounded ; ventral margin slightly curved or almost straight, and nearly parallel 
with the dorsal margin; posterior margin obliquely truncated, forming an acute angle 

' ' Album Pak'ont. de la Sarthe' (1867), p. 13, pi. xvi, fig. 3. 

- Owing to the difficulty of distinguishing the fossil forms of Cardita from Vaicricardia when, as 
in the case of nearly all the examples found in the Cretaceous rocks of England, the hinge is unknown, 
all the species are, for the present, referred to Cardita. 

10 



122 CJRKTACEOUS LAMELLTBRANCHIA. 

with the veiiti'al margin, and an obtuse angle with the dorsal margin. Umbones 
moderately prominent, curving foi'wards, bearing a carina which extends to the 
postero-ventral angle antl cuts off a flattened or concave area. Lunule ovate, 
rather large, nearly smooth. Escutcheon with a sharp edge. 

Ornamentation consists of narrow, rounded, radial ribs, separated by broad, 
flat interspaces, and crossed at rather distant intervals by strong, narrow, con- 
centric, lamellar ribs, which give rise to a scale-like projection where they join 
the radial ribs. The postero-dorsal area has similar concentric ribs, and a strong 
radial rib near the dorsal margin, and another near the middle of the area with 
smaller ribs between. 



Measurements : 
















W 


(2) 


(3) 


(4) 


(5) 


(6) 


Length 


20 


19 


19 


19 


18 


IG mm. 


Height 


14 


13 


12 


11-5 


12 


11 „ 



(1 — 6) Perwa-bed, Atherfield. 

Affinities. — G. fenestraia appears to be quite distinct from other Cretaceous 
species of Cardita, but shows some resemblance in form to G. tricarinata, d'Orbigny,' 
from the Cenomanian of Le Mans. The hinge and interior are unknown, and the 
generic position of the species is not free from doubt. Stoliczka remarks 
that ' G. fenestraia is not unlike a Venerupis.' 

Type. — From Peasmarsh, in the Museum of tlie Geological Society, Nos. 
2182, 2183. 

Distribufiun. — I'cnia-Xwd and Atherfield Clay of Atherfield. Atherfield WeiU 
of Peasmarsh and East Shalford. 



Cardita upwarensts, s]). nov. Plate XVIII, fig. 5. 

1883. Cakdita eotundataV W. Keejiincj. Foss., etc. Ncoe. Upwarc aud Brick- 
hill, p. 121, pi. vi, tig. 7. 

Description. — Shell subtriangular, inflated, height and length neai'ly e(|ual, 
inequilateral. Anterior margin i-ounded, passing, gradually into the convex ventral 
margin. Posterior margin truncated, oblique, not sharply limited from the postero- 
dorsal margin. Umbones prominent, strongly curved anteriorly, with a rounded 

1 ' Pal. Fran9. Terr. Grot.,' vol. iii (1844), p. 95, pi. cclxxxiii his., tigs. 5—7; Guorauger, ' Allmiu 
Palcont. de la Sarthe' (18G7), p. 13, pi. xvi, figs. Ifl, 20. 



CARDITA. 123 

carina extending to the postero-ventral angle, and cutting off a steeply-sloping 
postero-dorsal part of tlie valve. Lunule rather small, cordate, broader than long.. 

Ornamentation consists of about twenty-five radial ribs on the part of the valve 
in front of the carina ; the ril)s are strong and rounded, but are narrower than 
the interspaces. Both are crossed l)y regular concentric lamellre, which become 
prominent on the rilis. On tlie postero-dorsal area the ril)S are smaller, more 
numerous, and closer together; two of tliese ribs are rather stronger than the 
others, and divide the area into three parts. Length 21 mm. ; h(>ight 20-.5 mm.; 
thickness 17 mm. 

Affinities. — This species was doubtfully referred by W. Keeping to C. rotundafa, 
Pictet and Roux, but it differs from that form by its fewer and stronger ribs and 
more triangular outline (see p. 125). 

In form it resembles G. Dufiniana, d'Orbigny,^ bi;t the ribs on the postero- 
dor.sal area are smaller and moi'e numerous. In this respect, and in its shorter 
and less quadrate outline, it differs from G. neocominins, d'Orbigny.- 

Remarks. — I have seen only three examples of this species, two of which are in 
the Sedgwick Museum, and one is in the collection of Mr. J. F. Walker. 

Distribution. — Lower Greensand of Upware and Potton. 



Cardfta, sp. Plate XVIII, fig. 6. 

A specimen consisting of the united valves from which the ventral parts are 
missing was obtained by Leckenby from the rerna-hed of Atherficld, and is now 
in the Sedgwick Museum. It shows some resemblance to G. iqnrarensis (see 
above), but is more elongate and more distinctly carinate. 



Cabdita, sp. 

Two specimens of Garditn from the Hythe Beds of Maidstone are in the Museinn 
of the Geological Society. They were examined by Edward Forbes,'* who identified 
one with C. neocomiensis, d'Orbigny, and the other -svith C. quadrata, d'Orljigny. 
The specimens are similar in form to those species, but their state of preservation 
is too imperfect for satisfactory determination. 

1 'Pal. Franc. Terr. Crt't.,' vol. iii (1844), p. 88, pi. cclxviii, figs. 6— 10; Pictet and Campiche. 
' Foss. Terr. Cret. Ste. Croix ' (' Mater. Pal. Suisse,' ser. 4, 1866), p. 334, pi. cxxvi, figs. 4, 5. 
- D'Orbigny, ojj. cit., p. 85, pi. cclxviii, figs. 1 — 6. 
3 ' Quart. Jouru. Geol. Soc.,' vol. i (1845), p. 242. 



124 CRETACEOUS LAMELLIBRANCHIA. 



Cardita tenuioosta (Sowerhy), 1836. Plate XVIII, fi.i^^s. 7-14. 

1836. Venericardia tenuicosta. J. de C. Sowerhy. Traus. Geol. Soc, ser. 2, vol. 

iv, pp. 114, 259, 356, pi. xi, 
fig. 7*. 
1838. Cardium tetragonum, H. Michelin. Mem. Soc. geol. de France, vol. iii, p. 

102, pi. xii, fig. 3. 
1842. Venericardia teniticosta, A. Leymerie. Mem. Soc. geol. de France, ser. 2, 

vol. V, p. 25, pi. iii, fig. 0. 
1844. Cardita tenuicosta, A. (FOrbigny. Pal. Fran9. Terr. Cret., vol. iii, p. 87, 

pi. cclxviii, figs. 1 — 5. 
1846. Venericardia tenuicosta, A. Leymerie. Statist, geol. et min. de I'Aubc, 

pi. V, fig. 7. 
1850. Cardita — d'Orhigny. Prodr. de Pal, vol. ii, p. 137. 

1854. — _ J. Morris. Cat. Brit. Foss., ed. 2, p. 191. 

1855. — — G. Cotteau. MoU. Foss. de I'Yonne, p. 72. 
18GG. — —F.J. Pictet and G. Campiche. Foss. Terr. Cret. 

Ste. Croix (Mater. Pal. Suisse, 
ser. 4), p. 335, pi. cxxvi, figs. 
6—9. 
1871. — — F. Stoliczka. Paloeont. Indica, Cret. Fauna S. 

India, vol. iii, p. 287. 

Non 1842. Venericardia — H. B. Geinitz. Char. d. Schicht. u. Petref. des 

siiclis.-bohm. Kreidegeb., pt. 
3, p. 76, pi. XX, fig. 9 (C. 
Geinitzi, d'Orbigny). 

— 184C. Cardita (Venericardia) tenuicosta, A. E. Reuss. Die Versteiu. der biJlim. 

Kreideformat., pt. 2, p. 4, pi. 
xxxiii, fig. 16 (C corrugata, 
Eeuss). 

— 1873. Cardita tenuicosta, H. B. Geinitz. Das Elbtlialgeb. in Saclisen (Palaeon- 

tograpliica, vol. xx, pt. 2), p. 60, 
pi. xvii, figs. 11 — 13. 

— 1885. — (Venericardia) tenuicosta, F. Ni'iiliiuj. Die Fauna d. baltiseli. 

Ceuoman. (Palseout. Abhaudl., vol. 
ii), p. 29, pi. V, fig. 4. 

— 1889. — tenuicosta, A. Fritsch. Stud, im Gebiete der bolim. Kreide- 

format., iv. Teplitz. Scliicht., p. 78, 
fig. 62. 

— 1893. — — Fritsch. Titrf v. Priesener Schicht., p. 91. 

? — 1900. — — A. WoUemann. Die Biv. u. Gastrop. d. deutsch. u. 

hollilud. Neocoms (Abhandl. d. 
k. preussisch. geol. Land., N. F., 
pt. 31), p. 94, pi. iv, fig. 9. 



CARDITA. 125 

Description. — Shell more or less sub-quadrate, rounded, moderately convex, 
with the postero-dorsal portion compressed ; length greater than height ; moderately 
inequilateral. Postero-dorsal margin only slightly curved; posterior margin more 
or less truncated, passing by a regular curve into the ventral margin, which is only 
slightly convex and nearly parallel with the postero-dorsal margin. Anterior 
margin roimded. Antero-dorsal margin concave. Umbones curved anteriorly. 
Lunule ovate, nearly smooth. Escutcheon lanceolate, with a sharp edge. 

Ornamentation consists of 47 to 57 rounded radial ribs, which are separated 
by furrows of greater breadth than themselves ; near the postero-dorsal margin 
these ribs are rather closer together than elsewhere. In some cases the postero- 
dorsal part of the valve is divided into two parts by two ribs, which are more 
prominent than the others. At regular intervals concentric lamellse occur and form 
marked projections where they cross the ribs. Near the umbo these lamellfe are 
more widely separated, and near the margin, especially in large specimens, they 
are closer together than elsewhere. Sometimes faintly marked concentric ridges 
may be seen on the ribs between the lamellae. Margins of valves crenulate. 

Measurements .- 

(1) (2) (3) (4) (5) ((i) (7) 

Length . 30 27 25 24 24 23-5 28 
Height . 26-5 23 22 22 20 21 21 

(1—14) Gault, Folkestone. 

Affinities. — This species has more numerous ribs and is less inflated than 
C. neocomiensis, d'Orbigny and G. Diqiini'ina, d'Orbigny.i It possesses about the 
same number of ribs as G. Gonstanti, d'Orbigny,- but is less elongate and less 
inflated. G. rotundata, Pictet and Roux,^ differs from G. tenuicosta in being 
more inflated, and can be regarded as only an individual variation. Some examples 
found at Folkestone, which in other respects agree with G. temoicosta, are as much 
inflated as the type of G. rotundata. G. dathrata, Buvignier,* is a small form, but 
has the concentric laminae more widely separated than in even the young of 
G. tenuicosta. G. argonneiisis, Buvignier,^ is more compressed and has more slender 
ribs than G. tenuicosta. G. cenomanensis, d'Orbigny," is distinguished from 
G. tenuicosta by its broader ribs and more closely placed concentric lamellae. 

G. temoicosta has narrower ribs and broader furrows than the forms from the Chalk 

1 For references to figures of these species see p. 123, footnotes 1, 2. 

2 ' Pal. Fran9. Terr. Cret.,* vol. iii (1844), p. 89, pi. cclxix, figs. 1—5 ; Pictet and Campiche, ' Foss 
Terr. Crct. Ste. Croix' ('Mater. Pal. Suisse,' ser. 4, 1866), p. 337, pi. cxxvi, fig. 10. 

3 ' Moll. Foss. Grcs verts de Geneve' (1852), p. 443, pi. xxxiii, tig. 6. 

* ' Statist, geol., etc., de la Meuse,' Atlas (1852), p. 19, pi. xv, figs. 16, 17. 

5 Ibid., p. 19, pi. xxxii, figs. 1 — 3. 

« D'Orbigny, op. cit., p. 94, pi. cclxxxiii bis., figs. 1 -4. 



(8) (9) 


(10) 


(H) 


(12) (13) 


(14) 


23 22 


22 


20 


16 15 


15 mm 


19-5 20 


19 


17 


14-5 14 


13 „ 



126 CRETACEOUS LA]\rELLIBRAXCHIA. 

of Saxony and Bohemia wliicli have Ijoen referred to that species by Geinitz and 
by Renss. C icnuicosta of Reuss is the type of G. (Venencardia) bohemica, 
Griepenkerl.^ 

B,emarlvS. — Numerous specimens of C. tennicosta from Folkestone have been 
examined, and they are found to show a considcralile amount of variation in con- 
vexit}' and in relative height and length. 

Type. — The type came from the Gault of Folkestone, but cannot now be found. 

Distribution. — Gault (zones i, v, vii, viii, ix, xi) of Folkestone. Recorded by 
Jukes-Browne from the Cambridge Grcensand, and l)y Barrois fiom the Upper 
Greensand (zone of Schlanibachia rostrata) of the Isle of Wight. 



CAiiiniA CoTTAMnNA, (VOrhhjnij, 184-i. Plate XVIII, figs. 15, IG. 

1844. Caedita Cottaldina, A. d'Orhignij. Pal. Fran9. Terr. Cret., vol. iii, p. 01, 

pi. celxix, figs. 6 — 8. 
1871. — — F. Stoliczlca. Palseont. Indica, Cret. Fauna S. India, 

vol. iii, p. 287. 
? 1895. — c/. Cottaldina, i/. T/essCTi. Zeitsclir. der deutscli. geol. Gesellscli., 

vol. xlvii, p. 485. 

Bemarlis. — Examples of a species of Gardita, which is not uncommon in the 
Chloritic Marl of Dorset, appear to belong to G. Gottaldina, but their state of 
preservation is very unsatisfactory. Most of the specimens are internal casts, and 
in cases where parts of the shell are present the surface is very imperfect, so that 
the characters of the ornamentation cannot be clearly distinguished. M. Raoul 
Fortin informs me that the preservation is equally unsatisfactory in the Cenomanian 
of Rouen, from whence d'Orbigny's specimens were obtained. 

The shell is quadrate in outline, very convex, carinate, and somewhat longer 
than high. The ornamentation appears to consist of about 40 ribs, separated by 
interspaces of great width. 

G. Gottaldina may be distinguished from G. tennicosta (p. 124) by its fewer ribs, 
by the length and height being more nearly equal, and by the greater convexity of 
the valves. 

Measurements ; 

(1) (2) (3) 

Length . . 21 . 20 . 16-5 mm. 

Height . . 19 . 18 . 14 „ 
Thickness . 16 l.r5 . 12 „ 

(1—3) Chloritic Marl. (1) Chaldon, (2) Chard, (3) Balcombe. 
1 ' Palseont. Abhandl.,' vol. iv (1889), p. 58. 



CARDITA. 127 

Distribution. — Chloritic Marl of Balcombe, Cerne, Chaldon, Clialmingtoii, Cliard, 
Maiden Bradle}', and Maiden Newton. Recorded by Jukes-Browne from the 
Chloritic Marl and the zone of Schlocnbachia carians of the Isle of Wi"-ht. 



Cardita, sp. 

Specimens of (Jiirildn from which the shell has disappeared, but showing traces 
of the ribs, are found in the Chalk Marl of Ventnor, Folkestone, etc. These are 
too imperfect for specific determination. A specimen from Riugmer was figured 
by Sowerby,^ and was subsequently regarded by d'Orbigny- as an example of his 
G. ditbia. 

Somewhat similar specimens also occur in the Upper Greensand of Devizes. 



Cardita cancellata, Woods, 1897. Plate XVIII, figs. 17, 18. 

1897. Cardita cancellata, H. Woods. Quart. Jouru. Geol. Soc, vul. liii, p. 390 

pi. xxviii, tigs. 2 — 5. 

Description. — Shell oval, slightly inequilateral, inflated, postero-dorsal part 
compressed, faintly carinate; length rather greater than height; margins rounded. 
Umbones moderately prominent, curved anteriorly. 

Ornamentation consists of a large number of radial ribs sepai^ated l)y narrow 
furrows, and crossed l)y numerous concentric ribs, giving a nodular appearance at 
the points of intersection. The concentric ribs are moi'c distinct on the anterior 
part and the radial ribs more distinct on the median and posterior parts of the 
shell. Margin of valves finely crenulate. 

Measurements .- 

(1) (2) (3) 

Length . 18 . 16 . 13 mm. 
Height . 16 . 14-5 . 12 „ 
(1 — 3) Chalk Kock, Cuckhamsley. 

Ajjiinfies. — This species is more inflated and more rounded than G. tcnuicusla 
(p. 121), and possesses more numerous radial riljs with narroAV furrows and 
strong concentric ribs instead of lamina?. 

The concentric ribs distinguish G. cancellata fi'oni the forms desci-il)ed by 

1 ' Mill. Couch.,' vol. iii (1820), p. 106, pi. cclix, fij;. 3 (the orighiul is now in the Britisli Musoiim). 
Venericardia'i Maiitell, ' Foss. S. Dowiis' (1822), p. 12»->. 

2 'Pal. Fraiiv- Terr. Cn't.,' vol. iii (18-44), p. 92, pi. cclxx, H^s. 1—5. Uiu-rau-er, • .Ubuni 
Palcoiit. de la Sarthe' (18(37), p. 13, pi. xvi, tigs. 14—18. 



128 CRETACEOUS LAMELLIBRANCHIA. 

Geinitz ^ and by Reuss ^ as C. tenuicosta. The concentric ribs and the nodular 
character which they give to the radial ribs separate G. cancellata from Veneiicardia 
santoncnsis, Miiller.'' 

llemarlcs. — The specimens of C^. cancdlata are chiefly in the form of internal 
and external moulds ; wax casts of the latter show the character of the ornamenta- 
tion. In a few cases small portions of the shell are still preserved. 

Type. — From the Chalk Rock of Cuckhamsley, in the Sedgwick Museum. 

Distribution. — Chalk Rock of Cuckhamsley, Aston Hill, Chinnor Hill, Thick- 
thorn Hill (Bledlow), Boxnioor, Luton, and Wood Ditton. 



J'timiVv/— CRASSATELLITID^, X»a«. 

Gemis — Crassatbllites, /. F. Kriiger, 1823. 
(' Geschichte d. TJrwelt.,' ii, p. 466.) 

Ckassatellites DivisiENSis, sp. uov. Plate XIX, fig. 1. 

Description. — Shell subquadrate, very inequilateral, moderately long, convex, 
but with flattened sides, carinate. Anterior margin regularly rounded ; ventral 
margin nearly straight, oblique to the postero-dorsal margin ; posterior margin 
convex, oblique, forming an obtuse angle with the postero-dorsal margin, which is 
nearly straight. TJmbones rather prominent, curved anteriorly. Carina rounded, 
forming a gentle curve between the umbo and the postei'O-ventral angle. 
Posterior area moderately large, apparently not divided by a median rib. Lunule 
deep. 

Ornamentation consists of numerous, strong, regular, concentric ribs, separated 
by shallow furrows. On the posterior area the ribs appear to be narrower. 
Length 45 mm. ; height 37 mm. 

Affinities. — This species shows some resemblance to G. Guerangeri, d'Orbigny,* 

1 C. Geinitzii, cVOrbiguy, ' Proclr. Je Pal.,' vol. ii (1850), p. 239. For references to Geinitz's 
figures see above (p. 1'24). 

~ ' Die Verstein. der bohm. Kreidefomiat.,' pt. 2 (184-6), p. 4, pi. xxxiii, fig. 16. C. corrngata, 
Ecuss, ' Geogu. Skizzen aus Biilimeu,' vol. ii (1844), p. I'JO ; Giiiiibel, ' Alilmudl. d. k. bayeriscli. Akad.' 
(Miiuclieu), vol. x (1868), p. 568. Canlita {Venericardia) boheinica, Grit'peiikerl, ' Seiiou. KiJuigs- 
lutter' ('Palaeont. Abhandl.,' vol. iv, 1889), p. 58. See also C. Cottaldina, i'Orhigny, ' Vrodr. da 
Pal.,' vol. ii (1850), p. 161. 

•■' ' MoUusk. Unterseu. v. Braunschweig u. Ilsede ' (1898), p. 55, pi. vii, tigs. 10—12. 

* 'Pal. Frau9. Terr. Crct.,' vol. iii (1844), p. 76, pi. cclxv, figs. 1,2; Gucranger, 'Album Pak'ont. 
de la Sartlie' (1867), p. 13, pi. xvi, fig. 11. 



CRAS8ATKLLITES. 12<) 

Init is iiKiiv iii(M|iiilat('i-iil, the ventral margin is nearly straight, llie posterior 
mai'giii is more obliqne, and the posterior area is relatively smaller. It is much 
more inequilateral than ('. regularis, d'0rbign3^^ C. divifiiensi.s also resembles 
some of the varieties of C. macrodonta (Sowerby)- from Gosaii. 

Distribution. — Upper Greensand (zone of Sclilmnhacliia roxtrata) of Devizes. 
An imperfect specimen from Warminster (zone of Pecten asjier) probably belongs 
to this species. 



Ci!AssATi:rj,iTE8 viXDiNNENSis {d' Orhif/mj), 1844. Plate XIX, figs. 2, o. 

1844. Crassatella vindinnensis, A. d'Oihiijuy. Pal. Fran^. Terr. Cri't., vol. iii, 

ji. 79, pi. cclxvi, figs. 1 — 3. 
1850. — vENDiNNENSis, d'Orbigtiij. Prodr. tie Pal., vol. ii, p. 160. 

1867. — VINDINNENSIS, E. Gurnviger. Album Pali'ont. de la Saribc, 

p. 13, pi. \vi, figs. 9, 10. 
? 1868. — — C. W. Giimbel. Geo<^u. Beschreib. Ki'migreicbs 

Bajern, vol. ii, p. 766. 
1871. — — F. Sloliczka. PalBeont. Iiidica, Cret. Fauna S. 

India, vol. iii, p. 294. 

Deserijitiun. — Sliell sulKpiadrate, bnt trigonal without the posterior area, very 
inequilateral, convex, with rounded carina. Anterior margin rounded, passing 
gradually into the slightly curved ventral margin ; posterior margin oblique, some- 
what sinuous ; postero-dorsal margin nearly straight, forming an obtuse angle with 
the posterior margin. Lunule elongate, deep. Uml)ones prominent, incurved. 
Posterior area of moderate size, divided by a median rib into two parts, of which 
the anterior is concave. 

Ornamentation consists of strong, regular, concentric ribs, separated l^y narrow 
fnrrows. On the posterior area the ribs become very narrow and more or less 
lamellar, and the interspaces are broad and flat. 

Measurements : 

(1) (2) 

Length ... 31 .. 30 mm. 

Height . . . 26 . . 20 „ 

(1, 2) Duuscombe. 
Ajfiiiitirs. — This s]iccie.s is related to ('. Iltirrifiisis, d'Oi-i)igny,-' and ('. (luvraii- 

' Op. cit., p. 80, pi. cclxvi, figs. 4 — 7. 

2 Zittd, "Bivalv. d. Gosaugeb." (' Denkschr. d. k. .Akad. Wien, Matli.-Nat. CI.,' vol. xxv, pt. 2, 
1866), p. 150, pi. viii, figs. 2, 3. 

^ ' Pal. Fi-an9. Terr. Crct.,' vol. iii (1844), p. 77. pi. cclxv, figs. 3—5 ; Guurauger, ' Album Pali'out. 
de la Sarthe' (1867). \k 13, ].l. xvi, fig. 12. 

17 



]:;(i ("RKTACEOIIS LAMEI.I.I HIIANCHIA. 

gerl, d'Urbignv,' but the [JostciMoi' inarii'in is more (ilili(|ni' ami the ])i)st(_MMoi' ai'ca 
relatively .smaller. 

Bcmarlra. — The lamellar I'ilis on the postei'iur area are not mentioned l)y 
(rOi'l)iu,ny, but attention is ealled to them by (Juerauger. 

I have seen only five specimens, which were collected l)y the late ('..). A. Mej'er, 
and are now in the Sedgwick Museum, Cambridge. 

G. v'mdinnensis is the type of Conrad's- genus I'lichi/lluents. 

Types. — Fi'om the Cenomanian of Rouen and Le Mans. 

Dislributlun. — Cenomanian (Meyer's Beds 10 and 12) of Duuscombe, Devon. 



Cu'iiitfi — Anthonya, ir. M. iliihh, 18G4. 

(• Geol. Siirv. Ciiliroruia, Pateout.,' vol. i, ji. 181, pi. xxx, iig. 2;i().) 

Antiiony.\ ('.\ni'i.\x.\, sp. nov. Plate XIX, figs. 4, 5. 

hcxcriptinii. — Shell elongate, tajiering posteritM'ly, very inei|uilateral, much 
eoiupressed. Anterior margin slightly convex. Ventral margin long, moderately 
convex. Posterior margin short, truncate, forming angles with the ventral and 
dorsal margins. Postero-dorsal margin concave. Umbones acute, near the antei'ior 
end. A faint carina passes from the umbo to the postero-ventral angle and cuts 
off a flattened or slightly concave postero-dorsal area. 

Ornamentation consists of numerous narrow, regular, concentric ribs over the 
whole surface of the shell. The riljs are separated by furrows of greater width 
than themselves. 

Measurements : 

(I) (2) 

Length . . . 34 . . -7 mm. 

Height . . . 27 . . 14 „ 

(1, 2) Folkfstoue Beils, near Coiil Pdiiit. 

Alii nil Irs. — This specie's is distinguished from .1. ( 'uniiu'liiniii ((r()rbigny)'M)y 
the shorter anterior [larl of the sliell, the smallei- apical angle, and by the i-ibs, 
wliicli ai-e of v(\\\:\] or nearly eipial strength over the wliole surface. It is le.ss 
elongati' and has a siunller a[)ical angle than tlie type species A. etdlrijonitis, Cabb. 

1 Oj). cit., p. 76, pi. cclxv, figs. 1, 2; Gucrangcr, op. cil.. p. I'h pi. xvi, fig. 11. 

- 'Amer. Jouru. Couch.,' vol. v (1869), p. 47. 

3 'Pal. Frau?. Terr. Cret.,' vol. iii (1844), p. 74, pi. cclxiv, figs. 7—9 ; referrt-d to I'ti/choniija by 
Pictet aud Campiclie, ' Terr. Grot. St«. Croix ' (' Mati'r. Pal. Suisse," ser. 4, 1866), p. 357 ; E. G. Skeat 
ami V. Madson, "Jiir. Neoc. and Gault Boulder.s in Denmark" (' Dan marks geol. Undersiig.,' vol. ii, 
No. 8, 1898), p. 178, pi. vi, fig. 13. 



CYi'lUNA. l:«I 

Hcutdrlis. — Only two .speciiiicns have been seen, hulli of wliirli were collected 
by Mr. H. Keeping, and aic now in tlie Sedgwick Museum, Cambridge. 
Dlxtribiit'wit. — Folkestone Heds, near (Vipt Toint, Folkestone. 



Anthonya, sp. Plate XIX, fig. (3. 

IJescr'qitinii. — Shell elongate, tapering posteriorly, veiy incijiulatei'al, greatlv 
compressed. Anterior margin convex, rounded, passing gradually into the slightly 
curved ventral margin. Posterior margin short, truncate, forming angles with the 
ventral and dorsal margins. Postero-dorsal margin long, slightly concave. Umbones 
sharp, anterior. Carina indistinct. Postero-dorsal area narrow. Surface of shell 
smooth, except for growth-lines, which are rather more distinct near the anterior 
margin than elsewhere. 

Length, 38 mm. Height, 15 mm. 

Ajjiiiificti. — This species appears to be closely allied to A. CornueHaiia (d'Orbigny),' 
but does not possess the concentric ribs near the anterior margin. It diifers from 
^4. cantiana, sp. nov., in the greater length of the anterior part of the shell, the 
greater curvature of the anterior margin, the lai-ger apical angle, and the absence 
of concentric ribs. 

Remarks. — A left valve is the only specimen seen. 

Distribution. — Lower Greensand (Crackers) of Athcrficld. 



Familu-CYPRimDA], LnmnrL: 

Genus — Cvi'iMNA, Laninrcl-, 1818. 
(' Auiin. situs Vert.,' vol. v, p. 550) 

Cvi'KiNA Saussuki [l!niii(jiiii(rl), ISlil. i'late XIX, figs. 7 — lo. 

1821. DoNACiTES Saussuki, a. Brongniarl. Auu. ik's Mines, vol. vi, \t. 655, pi. 

vii, fig. 5 (uou Venus Haiitsurii, 
Goldfuss, 1840J. 
1854. Mactra saussuki, E. liencvier. Mi'ni. ^'i-ol. sur la Perte-ilii-KIione, p. 24. 
185(5. Ctpiuna Saussuiu, F. J. Piclcl and E. lienevier. Foss. Terr. Aptieu 

(Mater Pal. Suisse, 
ser. 1), \i. 73, pi. 
viii, tigs. 1 — 2. 



For references see p. 130, footuoto 3. 



l:!2 ("RKTACEOUS LAMELUBILXNCIHA. 

18(55. Cyprina Saussuki, F. J. Pirhl (uid G. Camp'n-he. Foss. Terr. Cri't. Ste. 

Croix (Matter. Pal. 
Suisse, ser. 4), p. 
220. 
— — — 11. t'uqinnid. Moll. Aptifii do I'Espagne, p. 113. 

Tk't>crij)tio)i.'- Shell ii.-^nally <if siniill or moderate size, snb-triangulur, roniHled, 
often cyreniforni, convex, more or less eonsideniLly inequilateral. T/iinulai- iuai\oin 
of moderate length, concave. Anterior margin regularly rounded, passing gradu- 
ally into tlie convex ventral margin. Posterior margin short, often more or less 
rounded, sometimes truncate, forming an angle with the vential margin, and not 
sharjily limited from the long postero-dorsal margin. Umbones pi'diuinent, l)i-(iad. 
Carina rounded, sometimes rather indistinct. Postero-dorsal area nariow. 
Lunular region deep, indistinctly limited. Escutcheon elongate, bounded by an 
inconspicuous carina. Hinge not seen. Oi-nanientation consists of grcnvth-lines 
and numerous minute radial ribs. 

Measurement!:! ; 





(1) 


{■2) (:i) (1.) (5) (0) (7) 


(H) 


(9) 


Length 


52 


49 40 38-5 38 33 20 


2.')-r, 


21 mm. 


Height . 


■10 


40 31 33 31 27 21 


21-5 


11) „ 


Thickness 


34 


31 27 2G 20 10 

(1, 2) PeniaA,M, Atherfiekl. 
(3— S)) Crackers, Atherfield. 




l-l' „ 



All'niUies. — This species is related to C. nuiaild (see ]>. 13 1), but the outline of 
the .shell is less distinctly triangular, the sides are less flattened, the ventral margin 
is moi'e convex, the und)ones are broader and not so high, the lunular mai'gin is 
not so long, and the carina is less distinct. 

ReDuirkfi. — The relative height and length of the shell, and cunse(iuently the 
outline, vary considerably. 

Much larger and more globose specimens (Plate Xl.X, fig. 1;'>) in which the 
carina is indistinct, are associated with the normal forms of ('. SuKssiiri, liut are 
less abundant. At first sight, especially w hen the shell is not (piile ])i'rl'ect, lhe.se 
appear to be distinct from ('. Saiifisuri, but after compai'ing a number of speci- 
mens 1 am led to the conclusion that they are only old individuals Avhich have 
attained a large size. 

Examples of C Sanssnri from Atherfield were idt'utified by I'ictet and 
C'am|iiche, but, hitherto, no record of the species a[i|>ears to have been made by 
any English writer. 

Ti/2)e. — From the Aptian of the Perte-du-Rhone. 

Plsfrihiifiint. — Lower (livensand {J'crii(i-])Ci] and Crackei's) of At hertield. 
Atherlield Beds of llaslemere and lledhill. 



palcxontooraphical Socict\^, 1007. 



A MONO (I RAP H 



OF THE 



CRETACEOUS LAMELLIBliANCHIA 



OF 



ENGLAND. 



BY 



HENEY WOODS, M.A. 

UNIVBBSITT LECTUBEE IN PAL^IOZOOLOOT, CAMBRIDGE. 



VOL. II. PART IV. 

CYPRINID7E, ISOCAEDHDJ:, LUCINIDtE, CORBID/E, IMCAIIDIIDI'; 
TELLINIDiE, MACTRID/E, AND YENERID^. 

Pages 133—180; Plates XX— XXVII. 



LONDON: 

PRINTED FOR THE PAL^ONTOGRA PHICAL SOCIETY. 

1907. 



FKINTED BT ADLARD AND SON, LONDON AND DORKING. 



CYPRINA. 133 



CvnjTXA SKDdwicKT (Wallrr), 18(;(;. Plate XIX, fi^'. 14. Plate XX, figs. 1-5. 

186C. Sph^ra Sedgwickii, ,7. F. WnUer. Ann. Mag. Nat. Hist., ser. 3, vol. 

xviii, p. 380, j>l. xiii, figs. 1, 2. 
1867. CvPEiNA ANGULATA, var., JT. G. Seelcy. Ibid., ser. 3, vol. xx, p. 27. 
1875. — Sedgwickii, W. Kcephuj in T. G. Bouncy. • Cambridgosliiro 

Geology,' p. 68. 
1883. — — W. Keeping. Foss., etc., Neoc. Upwarc and Brick- 

hill, p. 123, pi. vi, fig. 12. 

Description. — Shell more or lef?.'? oval, sometimes suli-triangiilar, rounded, inflated, 
slightly or moderately inequilateral ; length as a rule not greatly exceeding the 
height. Lunular margin of moderate length, concave. Anterior margin rounded, 
passing gradually into the convex ventral margin. Postero-dorsal margin moderately 
convex. Umbones prominent, l)road, curved inward and forward. Carina absent 
or indistinct. Postero-dorsal region convex, rounded. Lunule large, ovate, 
bounded by a faint groove. Escutcheon long, bounded by a more or less distinrf 
carina. Ornamentation consists of growth-lines. 



Meafivrcments 





(1) 


(2) 


(3) 


(1) 


(5) 


(C) 


(7) 


(S) 


(9) 


Length . 


3!) 


38 


37 


37 


34 


32 


31 


27 


23 mm 


Height . 


34 


31 


31 


32 


31 


26-5 


27 


21- 


20 „ 


Thickness 


29 


25 


26-5 






23 


24 




JJ 



(1 — 9) Lower Greensand, Upware. 

Affinities. — This species is closely related to, and may perhaps be only a local 
variety of G. Sanssuri (see above). The chief points in which it differs from the 
latter are (1) the carina is absent or indistinct, (2) the posterior margin is 
relatively higher, (3) the valves are usually more inflated, (4) the shell is usually 
less triangular in outline and less inequilateral. 

RemarliS. — The examples of C. Se(tgn-irl-i vary in relative height and length, 
and consequently in outline. The longer forms approach C. Savssiiri more nearly 
than the shorter forms. 

This species was placed in the genus Spha-ni by '^\v. .1. F. Walker, l)ut was 
subsequently referred to Gijimiia by Seeley and by "W. Keeping. 

Type. — From Potton, in Mr. J. F. Walker's collection. 

Distnhutio)). — Lower Greensand of Upware and Potton. 

rvrRiXA oi'.xrs.v, Kerpiurj, 1883. Plate XX, fig. <>. 

1883. Cyprina outusa, TT. Keepimj. Foss., etc., Neoc. Upware and Brickhill. p. 

124, pi. vi, fig. 13. 

18 



134 CRETACEOUS LAMELLTBRANCHTA. 

licmnrls. — G. i>htusa, ot" which I have seen two specimens only, close!}' re- 
sembles some forms of C. Saussuri, but differs in having narrower and less curved 
umbones. It also resembles the more elongate forms of G. Sechjunclii. 

Type. — In the Sedgwick Museum. 

Distrihntion. — LoAver Greensand of Upwarc. 



CvrKiNA rrxEATA, Smrrrh/, 183C. Plate XX, figs. 7-12. 

1836. Cyprina ctjneata, .7. de C. Sowerhy. Traus. Geol. Soc, ser. 2, vol. iv, pp. 

240, 341, pi. xvi, fig. 19. 

1849. — TRIANGULARIS, T. Browii. Foss. Couch., p. 207, pi. Ixxxv, fig. 2. 

1850. — CUNEATA, A. (VOrhigny. Prodr. de Pal., vol. ii, p. 161. 
1854. — —J. Morrh. Cat. Brit. Foss., ed. 2, p. 199. 

1865. - — F J. Pictet and G. Canqnche. Foss. Terr. Cri't. Sto. 

Croix (Matrr. Pal. 

Suisse, ser. 4) ]>. 

230. 
1870. — — F. Stoliczlca. Palasout. Indica, Cret. Fauna S. India, 

vol. iii, p. 193 [^Anisocardia {Veni€Ua)'\. 

Descripf ion . — Shell of small or moderate size, triangular, convex with flattened 
sides, carinate, considerably inequilateral. Lunular margin long, concave. Anterior 
margin regularly rounded. Ventral margin only slightly curved, sometimes 
with the posterior part concave. Posterior margin short, truncated, almost 
straight, nearly parallel to the height of the .shell, forming a right angle with 
the ventral margin and an obtuse angle with the long postero-dorsal mai-gin. 
Umbones prominent, high, curved considerably inward and forward. A distinct, but 
rounded, carina extends in a gentle curve fi'om the umbo to the postero-ventral 
angle. In front of the carina the shell is sometimes slightly concave. Postero- 
dorsal area narrow, sloping steeply except near the posterior margin. Lunular 
region deep, indistinctly limited. Escutcheon elongate, lioundcd by a small carina. 
Ornamentation consists of very fine growth-lines at regular intervals. 

Mraanrcments : 

(1) (2) (3) (4) (5) (G) (7) (.S) (9) (ID) 

Length . 48 3G 35 31 29 26-5 26 26 23 20 mm. 
Height . 40 29 29 26 24 20-5 21 19-5 20 16 „ 

(1—10) Blackdown. 

Affiniflrs. — The differences between C. Saiisnurl and this species are given 
above (p. 132). 

The form from the Meule de Bracquegnies which wiu-^ referred to 0. inii'/iiJii/it, 



CYPRINA. 1:55 

Sowc-Hiy, l)y Briart and Comet, ' appears to he more neaily related to C. cuneata 
than to C. uiKjidala. 

G. securiformis, Sluirpe, - is similar to C. cuneata, but its ventral niar-'in has a 
nmeli greater cin-vature. 

C. cuneata is mentioned by Stoliczka as a typical example of tlie sub-genus 
Veniella, Stoliczka. ^ The anterior right cardnial tooth, however, does not appear 
to bo so strongly developed as in the type of VcidcUa. 

Ttjpes. — The types came from Blackdown, but cannot now be found. 

Distribution. — Upper Greensand (zone of Schlu.'nhachia runtrata) of l>la(.-k(l(n\ n 
and lialdon. Upper Greensand (Meyei"'s Bed 2) of Westou Mouth (Devon). 



Cypeina cl.\xbiensis, sp. nov. Plate XXI, fig. 2; Plate XXIV, fig. 1. 

Descri[)llou. — Shell large, stout, oval, rather elongate, consideraljly ineipiiluteral, 
moderately convex. Antero-dorsal margin short, straight or slightly concave. 
Anterior margin well rounded, passing gradually into the convex ventral mai-gin. 
Posterior margin oblique, sul>truncate, more or less rounded. Postero-doi'sal 
margin rather long, slightly convex. Umbones broad, curved anteriorly, with a 
rounded carina extending to the postero-ventral extremity, and limiting a flattened 
or somewhat convex postero-dorsal area which slo[)es rapidl}' to the postero- 
dorsal margin, but more gradually to the posterior margin. Lunidar region 
excavated, not limited. Ornamentation consists of small concentric ribs. 

Hinge : in the right valve the anterior cardinal is conical, larger than the 
median cardinal, and placed below and separated from the latter; tlie posterior 
cardinal is oblique, laminar, and divided by a furrow. In the left valve the 
anterior and median cardinals are stout, the posterior cardinal is obliijue and 
laminar. 

Measurements (ajjproximate) : 

(1) (2) (■■<) 

Length . 99 . 80 . 74 mm. 

Height 75 . ()!• . 5(i „ 

Aljinilivs. — This species resembles C. Cuudanti, Dollfus,' from the Kimeridgian, 
1 Meulu (le Bracquegnies (' Mi-m. cour. et Mt'm. des. Sav. (.'traugers,' vol. x.\xiv, 1807). i>. Oy, jil. 
viii, figs. 2G— 28. 

- ' Quart. Jouru. Geol. Soc.,' vol. vi (1850), p. 182, pi. xxii, figs. 1—3. C. globom, Sharin; (ILiJ., 
p. 182, pi. XV, fig. 1) is recorded by Morris from Blackdowu, but I have seeu uo example of it. 

•■' 'Palffiont. ludica, Cret. Fauua S. India,' vol. iii (1870), p. 189. See also Meek. 'luvert. Cret. 
aii.l Tert. Foss. U. Missouri' (1876), pp. 147—152. 

■i ' Fauue Kimmrrid. du Cap de la Hcve ' (1863). p. 65, pi. x, figs. 6—8. De Loriol and Pellat. 
' Mou. Etages supur. Jiuuss. de Boulogue-sm--Mer ' (187-1). p. 42, pi. xii. fig. 14. 



136 CRETACKUUS LAMbJLLiUUAM'll 1 A. 

Ijut is much lari^vr ami stouter, and the luimlar reg-ion is more deeply excavated; 
also the uinliniies appear to have a greater anterior curvature. 

Type. — From Benniworth Haven, in the Sedgwick Museum. 

Bidrlhntiun. — Claxby Ironstone (zone of Bclemnitcs lateralh) of Benniworth 
Haven and Donnington. 



CyI'EIXA teali;ikxsi8, sp. no v. Plate XX, fig. Von, h. 

Dcscriptiuii. — Shell very thick, large, elongate, oval, regularly convex, very 
ine(|uilateral. Antero-dorsal margin concave. Anterior margin rounded, curving 
rapidly, passing gradually into the ventral margin. Posterior margin rounded, 
forming an obtuse angle with the long, slightly convex postero-dorsal margin. 
Umbones broad, anterior, curved inward. A faint carina extends from the umbo 
to the po.sterior end. Luuular region deep. Escutcheon large, deep, limited by a 
strong carina. Ornamentation consists of growth-ridges. 

Measurement^! : 

(1) (-') 

Length .... 105 .. 62 mm. 

Height . . . . 82 . . 49 „ 

(1, i) Tealby Limestoue. 

Affinifirs. — In its elongate form, and deep, carinate escutcheon this species 
resembles G. huluniensi.s, de Loriol,i from the Portlandian. 

Iiemarls. — There are two specimens in the Sedgwick Museum and one in the 
British Museum. The hinge has not been seen. 

Dldv'ibutiun. — Tealby Limestone of Walesby and Claxby, Lincolnshire. 



CvriiiXA, sp. Plate XXT, fig. 3. 

A large Gi/priiKi from the Tealby Limestone of Claxl)y is known by a right 
and a left valve, now in the Sedgwick Museum, and appears to belong to a distinct 
species. It shows some resemblance to G. niKjnbttn, Sowerby (sec page 141), Ijut 
differs from that species in the greater ventral slope of the postero-dorsal mai-gin ; 
the greater obliquity of the jiostcrior margin ; tie smaller ciirvature of the 
umbones ; the longer and less concave antero-dorsal margin ; and in the absence 
of a carina cutting off a postero-dorsal area. The surface of the shell is 
imperfectly preserved, but in places there is evidence of well-marked gi-owth- 
ridgcs. Length, 92 nnn. Height, 80 mm. 

' De Loiiol aud iVllat, ' Porlliiudicu du Boulogue-sur-Myr ' (18(JG), p. h-k pi. v, fig. 9. 



CYPRINA. l;'7 

CynuNA, sp. Plate XX, []g. 1 I-. 

A few spcciiiious of a small ( 'i/priuu, with the .shell iiii|)ei'lectly [irescrved, 
liave been found in tlie Sj)eetoii Clay (!_), 1). 

Cvi'KiXA ANGLICA, sp. nov. Plate XX, figs. 15, l(i. i'late XXI, fig. la, b. 

Description. — Shell of moderate size, oval, inflated, very inequilateral. Anterior 
margin rounded, forming a continuous curve with the convex ventral margin. 
Posterior margin less convex than the anterior, sometimes slightly truncated, more 
or less oblique, usually curving gradually to join the ventral margin. Postero- 
dorsal margin long, slightly convex. Antero-dorsal margin short, nearly straight. 
Uinbones broad, anterior, curving inward and forward. I'ostero-dursal part of 
shell slightly compressed; carina al)sent or indistinct, liiinuk' ovate, dei)ressed, 
more or less distinc-tly limited. (Jrnamentation consists of growth-lines. 

Measurement : 

(2) (.-5) (4.) 

41 . 38 . 32 
33 . 31 . 24 
26-5 . 24 . lG-5 . 

(1 — 0) Crackers, Alhwfield. 

Affinilii'K. — ('. iiu(jllr(i does not appear to be closely related to any other 
English species. Externally it shows some resemblance to G. (uujnlatn, 8owerby 
(see below), l)ut is of much smaller size, more elongate, with a more or less 
distinctly limited lunule, and either without a carina or with an indistinct carina 
near the innbones. 

Iiemarls. — Nearly all the specimens show the two valves united, so that the 
hinge and pallial line do not appear to have been seen by jirevious workers ; this 
probably accounts for the fact that in several collections the species has been 
referred to the genus Venus. A left valve, from which I have removed the matrix, 
shows that the hinge agrees with ('ii^iriint, and that there is no pallial sinus. 

Type. — In the Sedgwiek Museum, Cauibi'idge. 

Distribatiuu. — Lower Ureensand (Crackers) of Athcrfield. Atherfield Beds of 
Peasemarsh. 



CvriJiNA (Vkmlhaimha) pkotkxsa, sj). nov. IMate XXI, figs. 4 — 7. Text-figs. 

2U, 21. 

1845. Cyi'iuna .\NauLATA, E. Fm-hes. Quart. Joiirii. Gcol. Soe., vul. i, y. I'iO 

(^(iWi'm). 





(1) 


Length 


42 


Height 


35 


Thickness 


28 



(5) 


(6) 


27 


21 mm 


20 


M--3 „ 


14-5 . 


l»-5 „ 



138 



CJtETxiCl<:uL8 LAMELLlliKAAClllA. 



Descrqilion. — yiiell large, oval, convex, moderately inequilateral, anterior pari 
produced. Antero-dorsal margin concave. Anterior margin rounded, ])assing 
gradually into the convex ventral margin wliicli curves upward to join the 
posterior margin. Posterior margin i-ounded, sometimes forming a large and 
rounded angle with the ventral margin, but sometimes passing into it gradually. 
Postero-dorsal margin convex. Postero-dorsal part of valves compressed, some- 
times limited by an indistinct carina. Umbones prominent, curving forward and 
inward. Lunule indistinctly limited. Escutcheon narrow, deep, with a sharp 
edge. Ornamentation consists of growth-lines. 




Fm. 20. — Cijprina (Vcnilicardia) proUnsa, sp. nov. Lowi-r (JivcnsanJ (i'c)«u-)jud), AtliorCukl. 
Socls""ick Museum. Kiirlit valvt'. x -J. 



Measurements 
(1) 
lOG 

84 



Leni>th 

o 

Height 



(2) (3) (4) 

105 . 103 . 99 

89 . 91 . 88 

(1—6) Perna-hcd. Atlu'ilifkl. 
(0) Crackers, Atliorfiekl. 



(5) 


("!) 


75 


■ID mm 


60 


■10 „ 



AJfinUics. — The characters which distinguisli this species fVom (_'. (uujuhdii, 
Sowerby, are : the umbones are less anterior and the shell is less inequilateral ; 
the umbonal part of the shell is relatively smaller; the carina is less distinct; the 
anterior part of the shell is more produced ; the posterior part is more I'oundcd ; 
the ventral margin has a greater cui'vature; the shell is less inflated, so that the 
marginal parts of the valves meet at a smaller angle. The anterior i)art of the 
shell resembles that of C. tnuicafa, but tlie posterior part is more rounded, and 



CYPRINA. 



139 



the postero-dorsal margin has a greater ventral slope. G. ijrotensa belongs to the 
sub-genus Vcnilicardin, Stoliczka.' 

Type. — In the Sedgwick Museum ; from the Pernn-bed of Atherfield. 

Distribution.— Lower Greensand : rerna -bed of Atherfield and Sandown. 




Fia. 21. — C'ljprinn (Vtnilicardia) protensa, sp. nov. Lower Greensand {Pema-hci), Atherfield. 
Sedgwick Museum. Eight valve, x -J. 

Crackers of Atherfield. Ferruginous Sands of Slmnklin (Meyer Collection). 
Atherfield Beds of Peasemarsh. 



Cvruix.v SowEunvr, d'Orhign)/, 1850. Plate XXI, figs. S, 0. Text-fig. 22. 



183G. Cyprina ANG1JI.ATA, .7. iJi; C. Soirerhy. Trans. Geol. Soc., ser. 2, vol. iv, 

p. 128. 
1845. — E. Forbes. Quart. .Toiiru. Geol. Soc, vol. i. p. 24<) 

(parliin). 
1850. — SowERBYi, A. (VOrhigny. Proilr. iIp Pal., vol. ii, p. 78. 

18.54. — ANouLATA. J. MnrrSf. Cat. T.rit. Fos.s., e<l. 2, p. IHO {/lartim). 



Mensur erne lit. •: 



.s : 



Length 
Height 



(1) (2) 

71 . Gl 
GO . 51 . 
(1, 2, 4) Hvthc Beds. nvUic. 

(3) Lower Greeusaml, near Atherfield 



(3) 
50 

52 



(4) 

55 mm. 

■I'S „ 



Palteont. ludica, Cret. Fauna S. India.' vol. iii (1870), p. IW. 



140 



CRETACEOrS LxV:\rEIJJBR ANCHTA. 



liiniKirls. — Internal casts of Cijjirutu are found commonly in the Hytbe Beds 
of Hythe, etc. Those from the " rag " have their original form well preserved, but 
the specimens found in the softer greensand beds are more or less crushed. One 
example of tlie same species with the shell preserved has been obtained from the 
Eower Greensand between Atherfield and BlnekgaTig. The form of t1ie shell 



'';f*<^ 







Fio. 22.— Cypiinrt Smeerhyi, d'Oib. Lower Greensand, Parliam Park. Britisli Museum, No. 5933. 
Internal cast. Left valve, and dorsal view of both valves, x ^. 

resembles that of C. Uiwolatd (see below), but the anterior curvature of the 
unibones is considerably less, and the postero-dorsal margin of the shell is less 
convex. It is difiicult to determine satisfactorily the affinities of this species until 
more specimens with the shell have been ol)tained. It may l)e identical with the 
form from tlie Up])er Ajitian of 8te. Croix and tlie I'ei'te-du-RhAne referred l)y 



CYPRINA. Ill 

Pictet and Roiix ' to ^ '. ' yn/r;/.s/.s, LcyiiiL'rie, ami Ijy Pictet and Cainpiclie - to (J. 
anijulafa, Sowerby. English examples were identified with G. arifjiilala by J. de C. 
Sowcrby, Forbes, and Morris, but were regarded by d'Orbigny as belonging to a 
distinct species which he named G. Sowerhiji, and mentioned as types the 
specimens collected by Fitton from the Hythe Beds near Folkestone. G. Soiverbyi 
also resembles G. neocomiensu, d'Orbigny.^ 

Bhtribution.—Hyihe Beds of Hythe. Sandgate Beds of Pailiam Pai-k. Lower 
Greensand between Atherfield and Blackganff. 



^^"'"O' 



Cyfkixa (Venilicardia) ANCiULATA {Sowcrhij), 181k Plate XXII, figs. 1— i. 

Text-figs. 23, 24. 

1814. Venus angulata, /. Sowerhy. Min. Conch., vol. i, p. 14-5, pi. Ixv. 

1828. Cyprina angulata, J. Flcmimj. Hist. Brit. Animals, p. 4-14. 

1836. — — J. de C. Sowerhi/. Trans. Gcol. Soc, ser. 2, vol. iv, 

p. 240. 
1850. — —A. d'Orbiyiuj. Proclr. de Pal., vol. ii, p. 161. 

1854. — _ /. Morris. Cat. Brit. Foss., ed. 2, p. 199 (farlim). 

1870. — — i^. Stoliczka. Palaeout. Indica, Cret. Fauna S. India, 

vol. iii, p. 19.3. 

Non 1868. — - A. Briart and F. L. Cornet. Meule de Bracqiicgnies 

(Mem. cour. et Mem. dcs Sav. t'trangers, 
vol. xxxiv), p. 68, pi. viii, figs. 26—28. 

Description. — Shell large, sub-quadrate, rounded, very inequilateral, moderately 
inflated. Anterior margin rounded, passing quickly into the ventral margin, 
with which it forms a regular and continuous curve. Posterior mai'gin more or 
less truncated, slightly or moderately convex, usually olilique, and forming an 
obtuse angle with the postero-dorsal margin. Uml)ones large, broad, anterior. 
A more or less distinct carina passes from the umbo to the ])ostero-ventral 
angle, cutting off a postero-dorsal area, which slopes rather rapidly to the posterior 
margin. Lunular region more or less depressed, not limited. Escutcheon narrow, 
deep, limited by a sharp carina. 

Ornamentation consists of growth-lines. 

In the right valve the posterior cai'dinal tooth is large and divided ; the 
median cardinal is smaller than the anterior cardinal, and in most forms adjoins 

1 Pictet and Eoux, ' Moll. Foss. Grcs verts de Geuuve ' (1852), p. 444, pi. xxxiv, fig. 1. 

2 'Terr. Cret. de Ste. Croix ' (1865), p. 221. 

3 ' Pal. Franc. Ten-. Cret.,' vol. iii (1847), pp. 98, 759, pi. cclxxi. Afterwards referred U< C. 
bemensis, Lejmerie, see d'Orbignv, ' Prodr. de Pal.,' vol. ii (1850), p. 77. 

19 



1-1-2 



CRETACEOUS L.OrELLTBRAXCTTTA. 



the postcro-dorsal side of the hitter, but in examples in which the umbones are 
more anterior in position the median cardinal is dorsal to the anterior cardinal, 
and is almost continuous dorsally with the posterior cardinal tooth. 
Measurements : 

(3) (4) 

. 911 . 98 . 
86 . 8G . 
(1—8) BlackdowD. 

Affinities. — Specimens of Gijprlna from the Aptian and Gault of the Perte du 
Rhone and Ste. Croix were referred by Pictet, Roux, and Renevicr, to G. ervyensis, 
Leymerie, but were subsequently identified with C. auijitJitln hy Pictet, Renevier, 





(1) 


(2) 


Length . 


103 


. lO-i 


Height . 


92 


. 90 



(5) 


(6) 


(7) 


(8) 


9G 


89 


87 


82 mm 


86 


79 


79 


70 „ 



\ 





Fig. 23. — Cyprina (Venilicardia) angxdata (Sow.). Upper Greeiisaud, lilackilown. MusuuiiX uf I'ractical 
Geology, No. 18698. Right valve, and anterior view of both valves, x *. 

and Campichc.^ Pictet and Campiche, after an examination of specimens from the 
Gault of Nievre and Yonne, came to the conclusion that G. ervyensis, as described 
and figured by Leymerie- and d'Orbigny,^ must be regarded as a synonym of 
G. angulata. I have had no opportunity of comi)aring French specimens with 
examples from Blackdown, but so far as I can judge from the figures of G. eroyensis 
tliere appear to be some differences, consequently I do not at present feel justified 
in including G. crryensin as a synonym of G. anguhdd. 

1 Pictet and Rous, 'Moll. Foss. Givs verts de Geneve' (1852), p. 444, pi. xxxiv, fig. 1. Pictot and 
Keuevier, ' Foss. Terr. Aptieu ' (' Matt'r. Pal. Suisse,' ser. 1, 185(3-58), pp. 75, 177. Pictet and CampicLe, 
'Terr. Crct. Ste. Croix' ('Mater. Pal. Suisse,' ser. 4, 1805), p. 221. 

- ' Mem. Soc. gt'ol. de France,' vol. v (1842), pp. 5, 25, pi. iv, figs. 6, 7. 

3 ' Pal. Fraue. Terr. Cret.,' vol. iii (1844), p. 102, pi. cclxxiv. 



CYPRINA. j.i3 

G. angtdafa of Briart and Cornet appears to be closely related to C. aineaia, 
Sowerby (see p. 134). 

0. {Venilicardia) Jid-eni, dc Loriol,' from the Gault of Cosne, resembles some 
forms of G. angulata.- 

Beviarl-s. — G. aiK/ulafa varies in its relative height and length, and in I lie 
position of the umbones. The shell is usually stont, Init occasionally rathcf lliin. 
Sowerby gives a good figure of G. angnlata, except (liat the teeth, as pointed out 
by Rtoliczka, are not correctly drawn." 




Fig. 2t. — Cyprina (Venilicardia) angulaia (Sow.). Upper Greensand, Blackdown. Sedgwick Museum. 
Eight valve x ^. Tlie hinge of this specimen is shown on Plate XXII, fig. 2. 

Types. — From the Upper Greensand of Blackdown, in the British IMuseum. 

Distribution. — UjDiJer Greensand (zone of Sclda'iibachia rostrnta) of Blackdown 
and ITaldon. Recorded by Jukes-Browne from the TiOwor Gault of A\'iltshiro, and 
from the Upper Greensand of the Isle of Wight. 



CvrKiXA (VENnjr.\TjmA) ltnkoi.ata {Soirn-lii/), 18] 3. ?lat(> XXII, figs. 5 — 8. 

Plate XXIII, figs. 1,2. 

1811. Venus castrensis, J. Parkinariii. Organic Eemaius, vol. iii, p. 1H7 (uou 

V. cagtrensis, L.). 



1 ' Gavdt de Cosne ' (1882), p. 68, pi. ix, fig. 1. 

- Morris records Cyprina globosa, Sharpc, from the Gi-eonsand of Bliuk.lowu, l.ut I Iiiivc not seen 
any specimen from that locality. Morris, ' Cat. Brit. Foss.,' ed. 2 (18.54). p. 100. Sbarpo, 'Quart. 
Jouni. Geol. Sop.,' vol. vi (18-50), p. 182. pi. xv, fis,'. 1. 

^ From tlu> remark on Sowerby's figiire made 1>\- Biiart and Cornet (p. l!f>) I can only conclude 
that thi'v Iiail not seen sjiecimens of C. angulaUt. 



144 CRETACEOUS LAMELLTBRANCHIA. 

1813. Venus likeolata, /. Sowerby. Miu. Couch., vol. i, p. ^>7, pi. xx (upper 

figure). 
1828. — — /. Fleming. Hist. Brit. Auimals, p. 449. 

1836. Cypeina rostrata, J. de C. Soiverbij. Trans. Geol. Soc, ser. 2, vol. iv. pp. 

240, 341, pi. xvii, fig. 1. 
183C. Cytherea lineolata, Snverhy. Iliid., p. 240. 
1850. Cyprina rostrata, A. cVOrhicjmj. Prodr. do Pal., vol. ii, p. 161. 
1864. — — J. Morris. Cat. Brit. Foss., ed. 2, p. 199. 

1854. Cytherea lineolata, Mnrris. Il)id., p. 200. 

18C5. Cyprina rostrata, F. J. Picfet aud G. Cainpichc. Foss. Terr. Cn't. Stc. Croix 

(Mater. Pal. Suisse, ser. 
4), pp. 222, 229. 
1870. — — F. StoUczha. Paloeont. Indica, Cret. Fauna S. India, 

vol. iii, p. 193 (VenlUcarilla). 
1907. — lineolata, R. B. Newton. Proc. Malacol. Soc., vol. vii, p. 284, 

pi. xxiv, fig. 14. 

Non 1844. — —A. (VOrligny. Pal. Franc. Terr. Cn't,, vol. iii, p. 98, 

pi. fclxxi (Cyprina neocomiensin. 



d'Orbigny, Ibid., p. 759). 



Measurements .- 





(1) 


(-') 


(3) 


(4) 


Length 


71 


()7 


66 


52 mm 


Height 


Gl 


GO 
(1—4) Blackdown. 


58 


. 43 „ 



Affinities. — This species differs from G. nnfjnlata in its more prominent and 
more strongly curved umbones, in tlie shorter posterior margin and tlie greater 
slope of the postero-dorsal margin, and in the more deeply depressed luniilar 
region. IMic hinge also differs : in the right valve the median cardinal tooth is 
tlistinctly separated from the anterior cardinal and is dorsal to the latter and 
continuous with the posterior cardinal tooth ; the latter is either undivided or the 
division is indistinctly shown. 

Bemarlcs. — C. linedlatu varies considerably in the prominence and curvature of 
the umbones, and, as a result, in the outline of the shell. An extreme form was 
figured by J. de C. Sowerby as the type of ('. rostrata; in specimens in which the 
umbones are less ))rominent and their anterior curvature less pronounced the out- 
line of the shell becomes less triangulai-, and in some cases approaches that of G. 
nngvlata, but the differences in the liinge of the right valve and the greater depth 
of tlu' hiuular ivgioii appear to l)e present in all specimens. The average size of 
this species is considerably less than that of ('. (iiujiddta. 

The type of ^^;//^•^■ liiiniltilit, Sowerby (!'. castrensis, Parkinson), from IJlack- 
down, agrees willi tlic iioi'uial forms of G. riixlr(it<i, except for tlie presence of 



CYPRINA. 145 

numerous W-sliaped markint>-s on the surface. Tliese appear to l)e clue to the 
structure of tlie shell (possibly connected with colour markings), since they are 
seen only in specimens which are somewhat decorticated, and are in some cases 
present on one valve but not on the other, or are seen on the dorsal but not on 
the ventral part of a valve. 

Stoliczka' thought that Venns Hnnolnta was probably identical with Cijthpren. 
jilana, Sowerby, but the hinge and pallial line of the former prove conclusively 
that it belongs to the genus Gi/priua. 

Types. — From Blackdown ; Venus Uneolata in the British Museum ; (,'. rosfrtiln 
in the Bristol Museum. 

Distrihnfloii. — Upper Greensand (zone of Schloenbochia rostrata) of Blackdown. 



CvrruxA (Vi-^nilicardia) tkuncata (Suwry/ji/), 1836. Plate XXIII, fig. 3. 

183G. Venus ? truncata, /. dr C. Sowcrhy. Trans. Geol. Soc, scr. 2, vol. iv, 

pp. 242, 341, pi. xvii. fig. 3. 
1850. — suBTRUNCATA, A. irOrbiijiitj. Prodr. de Pal., vol. ii, p. 159. 

18.54. CvTnEREA TRUNCATA, /. Morris. Cat. Brit. Foss., ed. 2, p. 201. 
1865. Venus subtruncata, F. J. Piciet and G. Campiche. Foss. Terr. Cret. Stc. 

Croix (Mater. Pal. Suisse, ser. 4), p. 190. 
1870 — — ii". Stoliczka. Pateont. Indica, Cret. Fauna S. India, 

vol. iii, p. 161 (Caryatis). 

Affinities. ^=^—0. truncata is closely allied to, and probably only a variety of 
C. angidafa. The shell is thinner, the posterior margin higher, and the anterior 
part more produced than in C. anguluta. 

This species, or variety, has hitherto been referred to Yenva or Cijtiieren, but 
a specimen showing the hinge and pallial line proves that it is a Ci/priiia. The 
hinge agrees with that of (J. angulatn. 

An example collected by the late Rev. W. Downes (Plate XXTII, fig. 4) is 
more elongated and more inflated than the type of G. truncata, but agrees in other 
respects, and is probai)ly only an individual variation. 

jTy/jJC. — From Blackdown ; in the Bristol Mu.seum. 

Distribution. — Upper Greensand (zone of Schla'tibachia rostrata) of Blackdown. 



CvnaxA i,I(;ei!IKXSis, crOrbignij, 1844. 

Tntornal casts of a large Ci/prina have been found in the C'enomanian 
Siiiidstdnc (if Wilmington,- Devon, and in the cherty blocks in the Eocene Cnivel 

' • Cret. Fauna S. India,' vol. iii (1870), i)p. 1(J0, 1G9. 

- Jukes-Browne, 'Cret. Bocks of Britain,' vol. ii (1903). p. 129. 



14G CRETACEOUS L AIMELLIBRANCHIA. 

(derived from tlic Upper Greensand) of Aller Vale near Torquay. They have 
been identified with C. ligeriensis, d'Orbigny/ by Mr. Jukes-Browne, wlio has 
compared them with examples of that species from the Cenomanian of Vimoutiers 
and Orliiquet, and states that the agreement is very close. The English specimens 
also resemble C. Noudiana, d'Orbigny," of which a cast only is figured b}^ 
d'Orbigny, and was at first regarded as C. lifjcriemis^. An example from 
Wilmington is in the Sedgwick Museum. Otiiers from Aller Vale are in the 
'i\ir(|uay Museum and in the Sedgwick Museum. 



Cyi'Imna (Ykxif.k Ai;niA ?) quadeata, iVOrhvjinj, ISll. Plate XXIII, figs. G — 9. 

1840. TsocAEDiA CEETACEA, TI. B. Gcuiifz. Char. (1. Schiclit. u. Pdrcf. dcs siichs. 

Kreidegeb., pt. 2, ]>. 53, pi. xi, 
figs. 6, 7 (mow Goldfuss). 
1844. Cyprina qitadeata, A. iVOrhi(puj. Pal. Fran?. Terr. Crct., vol. iii, p. 104, 

pi. celxxvi. 
1850. — — — Trodr. de Pal., vol. ii, p. 161. 

— — — ' H. B. Geinitz. Das Quadorsaiidst. odcr Kroidogeb. in 

Deutseblaud, p. 156. 
18(35. — — F. J. Pictef ami G. Campiche. Foss. Torr. Cn't. Sto. 

Croix (Mater. Pal. Suisse, ser. 4), 
p. 225, pi. cxv, figs. 3 — 5. 
1870. — — J^. Stoliczka. Paloeout. ludiea, Cret. Fauna S. India, 

vol. iii, p. 193. 
1873. — — R. B. Geinitz. Das Elbtbalgeb. in Sachsen (Palfconto- 

grapbica, vol. xx, pt. 2), p. 62, pi. xvii, 
figs. 14 — 16. 
'^ 1877. — — A. Frit.'irh. Stud, im G-ebiete der buliiii. Krcidcfonnat. 

II Weissenberg. u. Maluitz. Schiclit., 
p. 116, fig. 70. 
? 1883. — — — Ibid., Ill Iscrsobieht., p. 100, fig. 65. 

1895. — — E. Tiessen. Zeitsclir. d. deutscb. gcol. Gescllscb., 

vol. xlvii, p. 486. 
1807. Aectica — n. Woods. Quart. Joiirn. Geol. Soc, vol. liii, p. 390, 

pi. xxvii, fig. 25, pi. xxviii, fig. 1. 

Dem-ij^tiov. — Shell sul)-rhomboidal, much inflated, rather strongly carinate, 
very inequilateral ; length somewhat greater than height. Anterior margin 
rounded, passing gradually into the slightly curved ventral margin. Posterior 

1 'Pal. Franc. Terr. Crct.,' vol. iii (1844), p. 103, pi. eclxxv, figs. 1, 2; ' Prodr. de Pal..' v..l. ii 
(1850), p. 161 ; Gucrangcr, 'Album Paleont. de la Sarthe,' 1867, p. 13. i>l. xvii, figs. 1, 5. 
- Op. r!l. (1844). pi. eclxxv, figs. 3, 4; op. cit. (1850), p. 195. 



CYPRINA. 



117 



margin truncated, 



hi"'li. 



Postcro-dorsal region flattened. Umbones pi-oniinent, 



anterior, curved inwards, 
concentric striae. 
Measurements : 



Lunnlar region excavated. 



Ornamentation consists of 





(1) 


(-') 


(3) (1) (5) (0) (7) 


Length . 


54 


40 


37 35 26 23 4(3 


Height . 


40 


41 


34 31 24 19 39 

(1—6) Gault, Folkestone. 

(7— !;i) Rye Hill Sand, Warmiuster. 

(10) Cbloritic Marl, MaiJeu Bradley 

(11) Base of Chalk, Chard. 



(«) 

10 



(9) 

20 
15 



(10) 

45 

38 



(11) 

58 mm. 
52 „ 



Affinities. — In G. ligeriensit^, d'Orbiguy,^ the umbones are less auterioi- in [nm- 
tion, and the angle between the posterior and the dorsal margins is larger than in 
G. (jnadrata. 

G. retjularis, d'Orbigny,- is distinguished from C. qudtlralti by its k>ss ine(jui- 
lateral and more regularly globose shell, by its less incurved umbones, and the 
smaller truncation of the posterior end. 

G. crassLcornis (Agassiz)'^ possesses a relatively higlier and less inequihiteral 
sliell, witk moi'e prominent umbones, which are not so nuicli curved anterioi'Iy 
as in G. quadrata. 

Ri'marlis. — The specimens from the Gault liave the shell more or less i)erfect]y 
preserved, but most of the examples from higher beds are, like the type, in the 
form of internal casts. The specimens found in the Chalk Rock are rather 
imperfect, but do not appear to differ specifically from those found at lower 
horizons. 

Type. — The locality of the type is not given by d'Orbigny, but he records 
specimens from the Ceuomaniau of Villers (Calvados), Rouen, St. Calais (Sarthe), 
etc. 

Distribution. — Upper Gault of Folkestone. Upper Greensand (zone of Scldwn- 
hachia rostrata) of Devizes {fide Jukes-Browne). Rye Hill Sand of Warminster. 
Base of the Chalk of Chard. Cldoritic Marl of Maiden Bradley and the Isle of 
Wight. Chalk Rock of Morgan's Hill near Devizes, Cuckhamsley, and Luton. 

1 ' Pal. Fran?. Terr, Cret.,' vol. iii (18-14), p. 103, pi. ccl.\xv, fi},'s. 1, 2 (not 3, 4). 

- Ibid., p. 100, pi. cel.x.xii, figs. 3—0 ; Tictet and Campiche, ' Foss. Terr. Cret. Sle. Croi.x ' (1805), 
p. "224, pi. cxv, figs. 1, 2. 

3 ' Etudes crit. Moll. Foss., Myes' (1842), p. 30, pi. viii/, figs. 5—10 ; Pictet and CauipicLe, * Terr. 
Crct. Ste. Croi.\' (' Matrr. Pal. Suisse,' scr. 4, 180.5), p. 220, pi. cxv, figs. 0—8. 



148 CRETACEOUS LAMELLIBRANCHIA. 

Genvft — TifAPEZirM, Mcgcrlc v. Muldj'i-ldt, 1811. 
(' Naturf. Frcuude zu Berlin Mag.,' vol. v, p. 68.) 

Trapezium ? akcadifoeme {Keeping), 1883. Plate XXIII, figs. 10, 11. 

1883. Cypeicaedia aecadifoemis, W. Keepimj. Foss. etc., Neoc. Upware and 

Bru'lihill, p. 120, pi. vi, (ig. (3. 

DcHcrqdiuii.. — Shell trapezoidal, iuHated ; length much greater than height. 
Dorsal and ventral margins nearly straight and nearly parallel. Posterior margin 
oblique, straight or slightly curved, forming an obtuse angle with the dorsal 
margin and an acute but rounded angle with the ventral margin. Anterior margin 
rounded. Umbones near the anterior end, much curved, with a strong, rounded 
keel extending to the postero-ventral angle. The part in front of the keel is 
slightly concave, giving a faint sinuosity to the ventral margin of the valve. The 
triangular part dorsal to the keel is compressed and flattened, and slopes steeply to 
the margin. Lunule cordate. Hinge not seen. 

Ornamentation consists of small, rounded radial ribs, and, at intervals, strong 
concentric laminar ridges ; both ribs and ridges are indistinct on the part dorsal to 
the keel. Length 21 mm. ; height 12*5 mm. ; thickness, 13 nun. 

Ajfiiiitics. — This species is more elongate, and the carina is more angular than 
in T. squamosum (see below). 

llonarks. — The only examples seen are the type and u specimen in Mr. J. F. 
Walker's collection. 

Ti/pe. — The type is in the Sedgwick Museum. 

Distribution. — Lower Greeusand, Upware. 



Tk.u'kziilm ? stiU.VMOSUM {Ki'i'piiiij), 1883. I'latc XXlll, iigs. 12—15. 

1883. CypEiCARDiA squajiosa, W. KfCjiiiKj. Fona., etc., Neoc. Upware and Brick- 

liill. p. 120, pi. vi, fig. 5. 

Descriiilldu. — Shell rounded-oblong, much inflated, highest near the posterior 
end. Dorsal margin nearly sti'aight; the posterior forms a regular curve, which 
passes into the slightly concave ventral margin. Dorsal part of anterior margin 
concave, ventral part rounded. Umbones prominent, anterior, much curved. A 
broad, rounded ridge extends from the umbo to the postero-ventral extremity and 
divides the shell into two parts. The part in front of the ridge is slightly concave, 
the part above is larger and convex. Lunule cordate. 

Ornamentation consists of small radial rihs, and, at rather distant intervals, 



(3) 


W 


13-5 . 


12-0 111 Ml 


11 


10 „ 


10-5 . 


9 „ 



TRAPEZIUM. 149 

strong concentric liiniell*. Tlic oriKunontation is indisliiicl on llic ]iai't alxjvc the 
rounded ridge. Margin of valve crenulate. 

MeasiU'i'iHcnts : 

(1) (2) 

Length . 15-5 . 14 
Height . 12 II 

Thickness . 10 . 1() 

(1 — 4) Lower GreeusanJ, Upwaro. 

.[(ji II 'dies. — Keeping coniparetl this species with (JanlUn iiajcoiiiirusis, d"Oi-l)igiiy, 
to which it shows some resemblance in general form. Bnt the faint radial ribs 
and strong concentric lamella', as Avell as tlie cliaraeter of the hinge, so far as it 
can be made out, seem to connect this species with Tntjicxiniii, ratlier tlian witli 
Gardita. 

Tijpe. — In the Sedgwick Museum. 

Distr'ibutiuii. — Lower Greensand, Upwai-e. 



Trai'KZIUM ? sp. riate XXIII, fig. IG. 

1883. Cypkicakdia striata, W. KcepiiKj. Fuss., utc, Nuoc. Upware aud Urickliill. 

p. 119. 

An imperfect left valve from the Lower (Jreensand of Upware, in the Sedgwick 
Museum, was identified by W. Keeping with Gi/pricardin driula (Geinitz) ' from 
the Ceiioniauian of Saxony. The ribs are fewer in nuiubei- than in the examples 
of C. striata figured by Geinitz. 



Ti;Ari:zirM TUArE/.oin.vLi': {lu'iinrr), 1811. Tlate XXIII, figs. 17— H». 

18-41. Crassatella TitAriizoiDALis, F. A. Itiiiiur. Die Versteiu. d. uorJ-deiitsL-h. 

Kreidcyelj., p. 74. pi. i.\, 

? 1847. — — -1- d'Aicluuc. Mi'm. Soc. i,'L'ol. du Franco, 

sur. 2, vi)l. ii. p. 302. 
1850. Cyi'KINA — if B. Geinitz. Das Quadursaudst. odor 

Kn-idogcb. iu Dcutsoli- 
laud, p. 168 (/ic(Wim). 
1854. C'ypRiCAKDiA - A. d'Ovbiginj. Prodr. de Pal., vol. ii. p. 240. 



1 • Char. d. Schicht. u. Potrof. des siichs. Kreide-eb.,' pt. 2 (1840). p. 52, pi. x, fife'. 3. Modiol,, 
cardiloiih->>, (ieiuitz, 'Das ElWliali^'elx iu Sa*;l)seu ' (• Palajoutoyrai.hica,' vol. xx, pt. 1. 1873), p. 218. 
pi. xlviii. fij,'s. 11—13 ; pi. .\iix, tigs. 11», 20. 



150 CRETACEOUS LAMELIJlUIAXriTIA. 

1873. Cyi'kina tkapezuidalis, H. B. Geinitz. Das Elbtbalgeb. iu Saelisen 

(PalBeoutographica, vol. xx, 
pt. 1), p. 2211, pi. 1, fig. 6 
(?5). 

1889. Cyi-kicakdia — E. HuhapJ'd. Die Mollusk. Aacheu. Kreide 

(Palseontograpliica, vol. 
xxxv), p. 179. 

1897. Teapezium teapezoidale, II. Wumh. Quart. Jouni. Geol. See, vol. liii, p. 

391, pi. xxviii, figs. 9, 10. 

1901. Cypeicaedia teapezoidalis, F. Shinii. Jalirb. d. k. pi-eussiscli. geol. 

Laudt'saust. fiir 1900, vol. xxi, 
p. 80, pi. vii, fig. 5. 

1902. — — A.WollemcDui. Liiueburg. Kreide (Abhaiidl. 

d. k. preussisch. geol. 
Laudesanst. N. F., Heft. 
37), p. 78, pi. ii, fig. 3; 
pi. iii, fig. 1. 

Descriplhni. — Sliell trapezoidal, rounded, inflated. Ventral margin sliglitly 
curved, roughly parallel to the dorsal margin, and passing gradually into the 
rounded anterior margin. Posterior margin oblique, forming an obtuse angle with 
the dorsal margin and an acute angle with the ventral margin. Umbones near the 
anterior end, much curved. A sharp, gently curving carina extends from the 
umbo to the posterior angle and cuts off a triangular and slightly concave area. 

Ornamentation consists of fine concentric lines. 

Measurements ; 









(1) 




(2) 


(3) 


Length 






25 


. 


23 


21 mm. 


Height 






17 


. 


14 


1-i' „ 


Thickness 


, 


, 


IG 


, 


15 


15 „ 




(1- 


-3) 


Chalk Kuck, 


Cuckliamslej. 





Affinities. — Wollemann considers that Tra2)ezium galicianum (Favi'e)' is not 
distinct from this species, but is founded on an older example than tlie type of 
T. lrfijie-:oi(l(il('. According to Wollemann, various changes in the form of the 
sliell take place during growth. Thus, iu the older specimens the valves become 
more convex, the length relatively less, the posterior margin less oblique, the 
ventral margin more curved, the outline less trapezoidal, and the umbones less 
curved. This view is probably correct, l)ut none of the English examjjles which I 
have seen pass beyond the stage represented by Eomer's type. 

Tn Trape'Mim tricarinatum (Romer)'- the umbones are less anterior in position 
than in T. tvapczoidalc. 

1 ' Moll. Foss. de la Craio de Lemberg ' (l8l5!l), p. 109, pi. xii, tig. 3. 

- ' Die Versteiu. d. uord-deutseli. Kreidegeb.' (1841), p. 74, pi. ix, fig. 23. 



ISOCARDIA. 



151 



Bemarl:^. — This species occurs in the f'halk Rock, l)iit is not common. All the 
specimens seen are casts, but one shows a fragment of shell. 

Ti/pe. — The type is stated by Romer to have come from the Pliiner-kalk of 
Strohlcn (Dresden), but Geinitz says that he has never found the species at that 
locality. 

BhtrihnHon. — Clialk Rock of Dover, Cuckhamsley, Aston Rowant, Princes 
Risborough, Thickthorn Hill (Bledlow), and TiUton i-ail\v;iy futting. 



i^.??H(7//— ISOCARDIIDJ^, dray. 

Genus — Isocardia, Lmnarch, 1709. 
('Mem. Soc. Hist. Nat. raris,' p. 80.) 



Isocardia similis, Sowerhj, 1826. Text-fig. 25. 



1826. Isocardia similis, /. de C. Sowerhy. Min. Conch., vol. vi, p. 27. pi. dxvi, 

fig. 1. 

— A. (VOrhujny. Prodr. de Pal., vol. ii, p. 163. 

— J. Morris. Cat. Brit. Foss., ed. 2, p. 204. 

— F. J. Pictet and G. Campiche. Foss. Terr. Crct. Ste. 

Croix (Mati'r. Pal. Suisse, ser. 4), 
p. 240. 

— F. Slolicxl-a. Palffiont. Indica, Cret. Fauna S. India, 
vol. iii, pp. 188, 194. 



1850. — 

1854. — 

1865. — 



1870. — 



A 



f 



1 





•/ > 



v 



^ 



Fio. 2.x-/sr>fanJi<. simxUt, Sowerby. Lower Greonsnnd, near San.lRnlo. KiKht v.ilvo. nn.l anterior view. 
British Miisomii (Nat. Hist.). Tlie Typo. NatunU size. 



i:)2 CRETACEOUS LAMELLIBRANCHTA. 

Drscrijdinn. — Slu'll convex, oval, longer than high. Antero-dorsal margin 
short. Anterioi- margin produced, somewhat pointed, rounded, curving rapidly- to 
join the slightly convex ventral margin. Posterior margin short, somewhat 
truncated. Postero-dorsal margin long, convex, with a considerable ventral slope. 
Umbo prominent, recurved. Lunnlar region deep. A faint carina extends from 
the imibo to the jiostero-ventral extremity. Ornamentation consists of growth- 
lines. Length 78 mm. Height 70 mm. 

Bemnrlcs. — The type, a right valve, now in the British Museum, is the only 
undoubted example of this species which I have seen. From the nature of the 
matrix there seems no doubt that this specimen comes from ihc vniiiimilatitm zone. 
The hinge cannot he made out satisfactorily, l^ut the form of the shell agrees 
closely with that typical of hocardia. 

Disfriliiition. — Lower Greensand (zone of BmiriUncoras mammihitnm) near 
Sandu'ate.' 



i^ar»%— LUCINIDiE, Fleming. 
Genus — Lucina, J. G. Brvtjuiere, 1797. 

(' Encyc. Metli., Vers,' pi. odxxxiv. Lamarck, ' Mi'm, Soo. Hist.. Nat. Paris,' 1799, p. 84.) 



LuciNA, sp. Plate XXIV, figs. 2, 3. 

Internal casts of a Lucina have been obtained from the Spilsby Sandstone 
(/.one of Bdemnitcs latomli.^) of Donnington and Claxl)y. A right valve with the 
shell preserved was found by Mr. Lamplugh in the Spilsby Sandstone at ITolton 
and ])robably belongs to the same sjiecies as the casts. The shell bears numerous 
small concentric ridges. 



Lucina, sp. Plate XXIV, figs. 4, 5. 

Some internal casts and a portion nf an external cast of Luciiin have been 

1 honiriVia f omnia, Forbes, 'Quart. Journ. Geol. Soc.,' vol. i (1845), p. 242, pi. ii, fig. 10, is 
Known only liy Ibe imperfect typo specimen which is now iu the Museum of the Geoloi^ncal Society 
(No. 21.')0), ami was obtaine.1 from the Lower Greensand of Alborfiolil. It was roforrod to Ojiix by 
•rOrbigny, ' Prodr. de Pal.,' vol. ii (1850), p. 118. 

I.-dt-anlia cryptocoraa, d'Orbii^ny, has Itcon recorded by BaiTois from the Upper (Jroousand way 
Devizes, Sec 'Terrain Cn't. suix'r. dc l"Anglelerrc ct .Ic I'lrlande' (187(')). p. 61. 



LUCINA. 153 

foiiiicl in the Lower Greensaiur nf Blackgaug, Shankliii, and I'liilunii I'ark. Tlie 
outline is nearly circular and tlie convexity small or inoileratc. The ornamenta- 
tion consists of concentric ribs and flat interspaces. 

LuciNA, sp. Plate XXIV, fig. G. 

A specimen witli the two valves united was ohfaincil by the late C. J. A. 
Meyer from the Lower Greensand (Ferruginous Sands) of Sliankbii, and appears 
to Ijelong to a distinct species. The shell is regularly convex, slightly higher than 
long, and the lunule is deeply depressed. The ornamentation consists of numerous, 
small, regular, concentric ribs. 

LiTfixA? scuLPTA, Phillip.% 1820. Plate XXTV, figs. 7—9. 

182D. Lpcina sculpta, /. Phillips. Geol. Yorks., j)}). 122, 170, pi. ii, fiij;. 1-'. 

(p. 252, C(l. 3). 
1844. — —A. d'Orhi.jtiy. Pal. Frauy. Terr. Crct., v,.l. iii, p. 118, 

pi. ccLxxxiii, figs. 1 — 4. 
18.50. — — E. Eichwald. Zeitschr. d. deutscli. geol. Gesollsch., 

vol. ii, p. 471. 
— — — A. cVOrbifjni/. Prodr. de Pal., vol. ii, p. 118. 

18,54. — — /. Morris. Cat. Brit. Foss., ed. 2, p. 208. 

1862. — — J. G. Chenu. Man. de Conchyl., vol. ii, p. 110, fig. .571. 

1866. — — F. J. Fidet and G. Campiche. Foss. Terr. Cret. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), 
p. 291. 
1871. — — F. Stoliczka. Palseout. ludica, Cret. Fauna S. India. 

vol. iii, p. 252. 
100(1. — — A. Wollemann. Die Biv. u. Gastrop. norddeutsch. Gaults, 

p. 277. 

Description. — Shell very convex, liighei' than long, with angular outline. 
Antero-dorsal margin long, concave. Postero-dorsal margin long, convex. Angles 
occur at the ventral limit of the lunule, at the junction of the anterior and ventral 
margins, near the posterior part of the ventral margin, and at the ventral limit 
and the middle of the escutcheon. Umbones high, prominent, sharp, curved 

1 Liicina arduennensis, d"Orl)igny, and L. Diqiiiiiam, d'Orbiguy, have heeu recorded by Toploy 
from the Lower Greensand of the Weald. I have not seen any specimens which could l)o ideutifie<l 
with those species. Two imperfect left valves from the Lower Greensand of Athertield, now in the 
Museum of the Geologi.'al Society, were rcferre<l hy Forties to L. glnhifoniils, Ixnnierio. Witlmut 
Letter specimens it is <lifficult to ■letermine the genus to which Forl«>s' six'cimens iiclong. See Forl)e.<*. 
•Quart. ,T..„n,. Geol. Soc." vol. i. (1H1.5). p. 240; Leyjnerie. 'Mem. Sw. gcol. de France." v..I. v 
(1842). p. 4, pi. iii, fig. 8. 



VA rRETACEOrS T.A:\rELTJBRAXrHTA. 

anteriorly. Ridges extend from the iinil)o to tlie angles at the margin of the 
valve; the parts between tlie ridges are flattened. Lnnule Inrge, ovate, divided 
into ail inner and an outer part l\y a ridge. Escutcheon wry large, consisting of 
a median lanceolate part which is much depressed and sejiarated by a sharp edge 
from a large concave outer portion. 

Ornamentation consists of broad concentric ridges which run parallel to the 
margin of the valve and end abrupt!)^ at the hnude and escutcheon. Ver}- fine, 
sometimes indistinct, ribs occur on the ridges and interspaces. 

Affinities. — Lucina sruljjfn is quite unlike any other Cretaceous species. Its 
angular outline and large concave escutcheon give it an unusual appearance. 
Externally it shows some resemblance to some species of Thi/nsirfiy^ but the hinge 
and adductor impressions are at present unknown. Stoliczka regarded it as 
probably a true Lucina. 

Jtemarlcs. — I have seen only four specimens, of which three are in the British 
Museum and one is in the Museum of Practical Geology. 

Tijitc. — The type cannot be found. It is stated to lia\e come from the Speeton 
Clay (Pzone of nch'ninites minimus). 

Pisfrihniion. — Lower Gault (Bed vi) of Folkestone. 



Lucina tenera (Smrrrhi), 1S8G. Plate XXIV, figs. 10—14. 

1836. Venus ? tenera, /. de C. Sowerhi/. Trans. Gcol. Soc, ser. 2, vol. iv, pp. lit, 

335, pi. xi, fig. 7. 
1854. — — J. Morru. Cat. Brit. Foss., ed. 2, p. 231. 

1865. — — (? Lucina), F. J. Pictei and G. Campiche. Foss. Terr. 

Crt't. St^. Croix (Mati'r. 

Pal.Suisse,ser.4).p.l8P. 

1870. — — (PCabtatis), F. ,S7o/.iV2/w. Palwont. lu.lica, Cret. Fauna 

S. In.lia, vol. iii, p. 160. 
1875. Lucina — A. J.JuJces-Brovme. Quart. Jouni. Geol. Soc, vol. xxxi. p. 

300, pi. XV, figs. 10—12. 

Description. — Shell oval, moderately convex, longer than liigh, inequilateral, 
the anterior part longer and higher than the postei-ior part. Anterior margin 
regularly rounded, passing gradually into the cui'ved ventral margin. Posterior 
margin somewhat truncated, forming an obtuse angle with the postero-doi'sal 
margin. Uml)ones of moderate size with a slight forward curvature. Lnnule 
elongate, depressed, limited by a carina. Escutcheon large, not distinctly limited. 

1 Axinvs, Sowerln- ; Cri/ptoihin. T\\r\i'n. 



LUCINA. 1 



J-) 





(1) 


Length . 


15 


Height . 


14 


Thickness 


8 



(1) 


(5) 


12-5 . 


<.l 


n 


7'5 


— 


■i-5 



Ornamentation consists of numerous, regular, strong, concentric ribs which become 
smaller near the antcro-dorsal and postcro-dorsal niai-gins. 
Measurements : 

(2) (3) . 

1-i . lo . iz-o . \i inin. 

12 . 11 . 

7 . G-5 . 

(1—5) Gault, Folkestone. 

Aj)inities. — In form and ornamentation this species resembles Jj. Sanctai-Crucu, 
Pictet and Campiche,' but is much smaller and relatively longer. 

Tijpc. — The tj-pe came from the (Jault of Folkestone, but cannot now be 
found. The specimens figured by Jukes-Browne are in the Setigwick Museum, 
Cambridge. 

Distriljiiflua. — Gault of Folkestone and Black Ven. Cambridifc Greeusand. 
Upper Greensand (zone of Scldeciibachia rostrata) of Devizes. 



LuciXA DoWNESr, sp. nov. Plate XXIV, figs. 15 «. — r. 

Description. — Shell oval or nearly orbicular, moderately convex, slightly iiieijui- 
lateral, longer than high, postero-dorsal part compressed. Anterior and ventral 
margins rounded. Posterior margin less convex than the anterior, forming an 
obtuse angle with the convex postero-doi-sal margin. Umbones of moderate size. 
Lunule elongate. Ornamentation consists of numerous regular, coucentrie, lamellar 
ribs separated by broad, flat interspaces with fine concentric ribs. 

Measurements : 

(1) (2) 

Length . 32 . 20 mm. 

Height . 28-5 . 24 „ 

Thickness . 14 — ,, 

(1, 2) Blackd.iwii. 

AlJiuillrs. — This species resembles L. ('iiniiirli,nui., d'Orbigny,' \'ix>n\ the 
Neocomiaii, Imt the undjones are less prominent and the shell is less iiRMHiilateral. 
It is also similar to L. submimismalis, d'Orbigny,'^ from the Aachen Greensand, 
l)ut the ribs are more numerous and the antero-dorsal margin has a greater 

' " Terr. Crt't. Ste. Croix" (' Mater. Pal. Suisse," ser. -4, 18tJG). p. 28;t, pi. cxxii, fig. 8. 

2 ' Pal. Fi-au9. Terr. Crct.,' vol. iii (1844), p. 110, pi. cclxxxi, figs. 3—5. 

•* Holzapfel. " Die MoUusk. Aacheu. KreiJe " (' PalsEoutographica,' vol. xxxv, 1880), p. 187. 
pi. xix. figs. 1—3. Eavn, ' Mollusk. i Daumarks Kridtafl. I. Lamellil.r.' (PJ02), p. 12!i, [.l. iv. 
tiu'. 21. 



lOG CliK'l'ACL'^OLS LA.M KI.LI IJIi ANCHIA. 

vt'iili'al slii|R'. TIk' ribs arc iiioiv iiuiiicrdus lliaii in Lncin(( Xrrcis, d'Orljigu}',^ 
I vmw t lir (V'lioiiiaiiiaii. 

I'islribittidu. — Uppor Greciisaiid (zone of Scltlirulincliiii nistfdfn) ol' IJlacktlowii. 
Up[)er Greensaiul near Ijyiiie Regis. 



LuciNA I'lSU.M, Soircrlii/, ]S'M>. Plate XXIV, figs. ](J — !',•. 

1836. LuciNA I'isuM. /. ih C. Sowirhij. Traus. Cleol. Soc, ser. i, vul. iv, iip. 241, 

a-11. 1)1. xvi. fig. 14. 
1850. — — A. d'Orhlyiii/. I'milr. <k' Pal., vol. ii. p. l(i-2. 

1854. — —J. Morris. Cat. Brit. Foss., ed. 2, p. 208. 

1871. — — F. Stolivzlai. Palauout. ludica, Cret. Fauua 8. India, vul. 

iii, p. 252. 

Noll 1814. — — A. d'Orhiijnij. Pal. Fi-au9. Terr. Cret., vol. iii, pi. L-cl.\.\xi, 

figs. 3 — 5 {L. Cornuvliana, p. llli). 
r — 1868. — — A. Brlarl iiikI F. L. Cornet. Meide de Bracqueguies (Mem. 

cour. et Mi'Ui. des Sav. utraugers, vol. 
xxxiv), p. 69, pi. viii, figs. 18 — 21. 

Dcacriptioii. — Sliell .small, verj^ convex, with nearly circnlar outline, slightly 
ine(|uilateral ; length and height nearly ecpial. Anterior and ventral niargin.s 
forming a regular curve ; posterior margin slightly truncated, forming an obtuse 
angle with the postero-dorsal margin. Umbones rather large. Lunule ovate, 
broad, depressed. Escutcheon indistinctly limited. Ornamentation consists of 
concentric ribs, with "Towth-rinas at intervals. 



»_11 LliV, X±t_7.Z>j **J.LJll i;i»_'>* Lll 


lllI^O ClU IIILV. 


_ I * tl JC* 




\Ieasnrcm('iiti< : 










(1) 


(^) 


(:') 


Length 


5 


4-5 


!■ mm. 


Height 


4- 9 


4-;J 


4 „ 


Thickness 


:3-5 


3 


2-!) „ 



(1—3) Blackdowu. 

li'tiiiarls. — The form referred to L. jjmtin by Briart and Cornet is ninch larger 
llian the English exam])les of that species, and also differs in its relatively longer 
and more compressed shell. 

Ti/j)r. — From Blackdown ; in the Bristol Museum. 

Di.'i/riliiitioii. — Upper (jreensand (/.one of Sclihriiliitclun rosti-ntn) of Blackdown. 

1 Trodr. de Pal.,' vol. ii (IS.W), p. 162. Gu.'-raugvr, 'Alhuiii Pal.'.mt. du la SaHlie" (1867), 
p. 12, [il. XV, fig. 15. The hinge figured by Gut'ranger does not agree with Liiclna. Stoliczka suggests 
that this species belongs to (Jijprimeria, see ' Palieont. Indica, Cret. Fauna S. India' (1871), 
pp. 164, 253. 



SPHiERA. 157 



■ Geniis — CoRHif'ELLA, J. Morn's 'iinl J. Li/rrtf, 185:"!. 
('Moll. Great Ool.,' pt. ii, p. 04) 

COEBICELLA 0LAXI3IENSIS, sp. iiov. Plate XXIV, figs. 20 — 28. 

Descri2}tion. —8he\l oval, regularly convex, sligLtly inequilateral, anterior part 
ratlier larger than the posterior part, length equal to nearly 1^ times the height. 
Anterior margin rounded. Ventral margin convex, curving rapidly to join the pos- 
terior margin which fatms an angle with the nearly straight postero-dorsal margin. 
Umbones broad, inconspicuous, scarcely curved, close together. Surface of shell 
smooth except for growth-lines. 

Measurements : 

(1) (2) (3) (I) 

Length . 38 . 37 . 30 . 27 mm. 
Height . 26 . 25 . 21 . 19 „ 
(1 — 4) Claxby Ironstone, Bcnniworth Haven. 
Remarlcs. — The genus Corbicella does not appear to have been recognised in 
deposits of Cretaceous age, but since it is present in tlic Portlandian its occurrence 
in the lower part of the Speeton Series of Lincolnshire causes no surprise. 

0. claMensis is similar in outline to some forms of G. Pcllati, dc Loriol,' from 
the Portlandian. 

Type. — In the Sedgwick Museum, Cambridge. 

Disfrihufion. — Spilsby Sandstone (zone of Belomnites lateralis) of Claxby and 
Donnington. Claxby Ironstone (zone of B. lateralis) of Benniwoith Haven. 

Genus— iivuA:T..\, J. Hoircrhi/, 1822. 
('Min. Conch.,' vol. iv, p. 41.) 

SrajiiiA coiiiirGATA, Scm-crh;/, 1822. Plate XXIV, fig. 24; Plate XXV, figs. 1,2; 

text-fig. 2(3. 

1822. Sm^TiKA CORRTJGATA, J. Sowcrhy. Min. Concli., vol. iv, p. 42. pi. cccxxxv. 
1842. Venus cordiformis, A. Lcyweric. Mrm. Soc. gcol. dc Fi-ancc, ser. 2. vol. 

v, p. .5, pi. v, fig. 8. 

' De Loriol and Pellat, ' Jui-ass. de Boulognc-sur-mer ' (1875), p. 67, pi. xiv. fig. 12. 

21 



ir.S rRETATEOFS LAMELLTBRANCHIA. 

1842. Cakdium oallopeovinciale, P. Maihcron. Catal. Poss. du Depart, des 

Bouclies-du-Rhone, p. 155, 
pi. xvii, fi<,'.s. 1, 2. 

1844. CoRBis conDiFORMis, A. iVOihiijiiij. Pal. Frau9. Terr. Crut., vol. iii, p. Ill, 

pi. cclxxix. 

1845. — COEEUOATA, E. Forhes. Quart. Journ. Geol. Soc, vol. i, p. 239. 
1850. — — cVOrhifjny. Prodr. de Pal., vol. ii, p. 78. 

1854. Sph^ea — J. Morris. Cat. Brit. Foss., ed. 2, p. 224. 

1865. Cordis — G. CoUeau. Moll. Foss. de I'Yonne, p. 80. 

185G. — —F.J. Pldd nmJ E. Renevicr. Foss. Terr. Aptien (Matrr. 

Pal. Suisse, ser. 1), j). 7(5, pi. viii, 
fig. 3. 
1859. — coEDiFOEMis, /. Vilanova-y-Plera. Mem. geog.-agric. de Castellon, 

pi. iii, fig. 13. 
18G5. — coERUOATA, H. Coqnand. Mou. Aptien de I'Espagne, p. IIG. 
18CC. FiMBEiA — F. J. Picfet and G. Campiche. Foss. Terr. Crc't. Ste. 

Croix (Mater. Pal. Suisse, 
ser. 4), p. 279. 
18G9. Pal^ocoebis coedifoemis, T. A. Conrad. Amer. Jouru. Coucli., vol. v, 

p. 101. 
1871. SiMLTiRA coREUQATA, F. SloliczJca. Palooout. ludiea, Cret. Fauna S. India, 

vol. iii, pp. 247, 252. 
V 1877. CoEBis ef, COERUOATA, G. Bolim. Zoitschr. d. deutscli. geol. Gesellsch., vol. 

xxix, p. 240. 
1897. — coEEtTGATA, 7v. Gerhavdt . Neues Jalirb. fiir Min., etc., Beil.-Bd. xi, 

p. 186. 
1899. Fimbria — A. WuJlcmann. Zeitschr. der deutscli. geol. Gesellsch., 

vol. li, p. 592. 

Description. — Shell large, stout, inflated, subglobular, slightly inequilateral, 
height and length nearly equal. Anterior margin rounded, forming an angle with the 
hinge-margin, and passing gradually into the ventral margin with which it forms 
a regular curve. The ventral margin curves rapidly towards the posterior margin, 
Avhich makes an obtuse angle with the hinge-margin. Lunule flattened or depressed, 
with a swollen lower margin which is separated from the rest of the valve l)y a 
furrow. Escutcheon triangular, limited by a furrow which passes from the umbo 
to the posterior margin. Umbones large, ])rominent, ciu'ved anteriorly'. Ornamen- 
tation consists of broad, strong, unequal, concentric ridges which arc more numerous 
on the middle than on the anterior and posterior parts of the shell. The concentric 
ridges are crossed l)y numerous, small, radial ril)s. 

Measurements : 

(1) (2) (3) (4) 

Ecnglh 95 . 84 . 80 . 70 mm. 
Heiglit 93 . 8:3 . 77 . G8 „ 

(1 — 4) Lower Greeiisninl, Atlierficld. 



SPII^RA. 



150 



Remarlx. — This species is tlio type of the genus Sjihmru. Tt is fairly coiiiiikhi 
in the Ferna-hed of the Isle of Wight. A young example is figured by d'Orhigny. 

Ti/pr. — The type was obtained by Professor Sedgwick from the 7V/-y(((-bed of 
Sandown, but cannot now- 1)0 found. 




Fiu. 2ij.—t>phxra con-wjala. Sow. Lower GroensanJ, iioiu- Ilythe. Miisoiuu of I'nictical Guology, 

No. I'JTIG. Dorsal view, x -J. 

Bidriblllioll.—Lo^ycr Greensand {I'cnia-hcd and Crackers) of Alherlield ; also 
recorded by Fitton from Beds viii and xiv, Hythe Beds of Hythe and Maidstone. 
Eecorded by Topley from the Atherfield Beds of Peasmarsh and Shalford ; the 
Hythe Beds of Lympe ; and the Sandgate Beds of Sandgate.' 



Si'UJiiiA, sp. Plate XXV, fig. 'S. 

A small specimen from the Chalk ^Marl of Clmrd appears to l)elongto a distinct 
species. It is much smaller than S. covriKj'dii, also relatively longer, more ovnl m 
outline, and less inflated. The escutcheon is not defined, the lunule is small or 
absent, and the antero-dorsal margins are thick and prominent. The concentric 
ridges resemble those of 8. cornniala,h\.\ii\iQ radial ribs are more distinct. Length 
IG'5 mm. ; height 14 mm. ; thickness 12'5 mm. 

1 The type of Corhis ? fibrosa, Forbes, from Peasmarsh, is in tlie Museum of the Geolo^'ical 
Society (R 215-1), but is too imperfect for deteriniuatiou. Forbes, 'Quart. Jouru. Geol. Soc.." vol. i 
(184.5), p. 239. 



ICO CRETACEOUS LAJilELLlliKANCHIA. 



0'c'M(«— MUTIELLA, Slulic::lca, 1871. 
('Palaeout. ludica, Cret. Fauua S. India,' p. 247.) 

MuTiELLA ? CANALICULATA (Sowerbi/), 183G. Plate XXV, figs. 4 — G. 

1836. Peteicola canaliculata, /. de C. Sowerby. Trans. Geol. Soc, sor. 2. vol. 

iv, pp. 241, 341, pi. xvi, 
fig. 11. 

— — NUCiFOEMis, Sowcrhij. liiitl, pp. 241, 341, pi. xvi, lig. lU. 
1850. Cakdium canaliculatum, A. d'Orhiijnij. Prodr. de Pal., vol. ii, j). 1(J3. 

— — NUCIFOKME, d'Orhijni/. Ibid., p. 163. 

1854. Petkicola ? canaliculata, /. Morris. Cat. Brit. Fuss., ed. 2, p. 220. 

— — NUCIFOEMIS, Morris. Ibid., p. 220. 

1866. Caedium canaliculatum, F. J. Pictet and G. Campic/ii;. Foss. Terr. Crct. 

Ste. Croix (Mater. Pal. 
Suisse, ser. 4), p. 270. 
1865-6G. Petkicola nucifoumi.s, Pictet and Campiche. Ibid., pp. 163, 276. 
1870. — canaliculata (Caedium), F. UtoIiczJca. Palajout. ludica, 

Cret. Fauna S. India, vol. 
iii, p. 141. 

— — NuciFoKMis {'f CoKBis), StolicxJia. Ibid., p. 141. 

Description. — Shell iiiHated, outline mure or less orbicular, hie(juilateral, length 
and height eciual. Margins rounded, xlnterior margin less convex than the pos- 
terior margin. The latter makes an obtuse angle with postero-dorsal margin and 
curves rapidly to join the ventral margin. The margin in front of the umbo 
expands. Umboues large, contiguous, curving inward and forward. No lunule. 

Ornamentation consists of numerous, regular, radial ribs, separated by narrow 
furrows, and crossed l)y narrow concentric ridges which ai'c more prominent 
on the posterior part of the shell than elsewhere. Inner margins of the valves 
crenulate. 

There are two cardinal teeth in the left valve and one in the right. Behind 
the umbo a long, nearly straight, sharp ridge forms the inner margin of the 
ligament groove. 

Measurements .- 

(1) (-') (a) 

Length . 20-5 . I'J . 17 

Height . 20-5 . 19 . 17 . 

^1—4) Blackdowu. 
Affinities. — The generic position ol' this species has been for a long time a 
matter of doul)t, l)ut no one appears to have accepted Sowerl)y's view. The 



(I) 




1-1-5 . 


]() mm 


14-5 . 


10 „ 



MUTIELLA. Kil 

species is rare, and the opinions expressed by various authors appear to have Ijeeu 
based entirely on the figures given by Sowerby. 

The hinge is similar to that of MutielUi coarctata (Zittel),' but shows some i)oints 
of difference : thus the transverse corrugations or teeth on the expanded anterior 
margin appear to be absent, and the terminal posterior lateral tooth cannot be 
recognised with certainty. The points of resemblance, however, and the similarity 
in the form of the shell and the character of the ornamentation seem suflicient 
to justify the assignment of this species either to Mafielhi or to a closely 
allied genus. 

From the figures given by Sowerby, Petiicola unc'ifortim appears to differ con- 
siderably from P. cdiiallcnlata, but after an examination of the type of the former 
I am led to the conclusion that it is not specifically distinct from the latter ; it 
differs only in being more inequilateral, and the apparent difference in the uiiia- 
mentation is due to the imperfect preservation of the surface of the shell in 
1'. )iiicifoniiis. 

Tii[ics. — From Blackdown. The type of J'ctricukt caiudicniata cannot be found. 
The type of P. nuclj'ormls is in the Bristol Museum. 

DistribHtioii. — Upper Greensand (zone of Scldamhacldd rostrala) of Blackdown, 
and Peak llill, near Sidmouth. 



MuTiiiLLA larrrxMATA {(rOrhiijin/), 1 8^1-4. 

1844. Coums ROTVSBXTA, A. d'Oihi(jinj. i'ul. Fium;. Terr. Cix't., vol. iii, \> Ilo, 

pi. cclxxx, figs. 1— i. 
1850. — — — Prodi-, de Pal., vol. ii, p. 1(32. 

18G7. — — E. Gtiiramjcr. Album Piilcout. do la Sarthe, p. 15, 

pi. six, figs. lU, 11. 

1870. — F. Itinner. Geol. v. Obersdiles., p. 3i0. 

1871. MuTiELLA KOTUNUATA, F. StoUczkci. Palujout. liidica, Cret Fauua S. ludia, 

vol. iii, pp. 247, 252. 
1896. CoEBis KOTUNDATA, A. J. Jukes-Broione and W. Hill. Quart. Joiu-u. Geol. 

Soc.,vol. lii.p. 153. 

A portion of a right valve of MiUicUa rotuiulata from the Ccuomanian (Bed 11) 
of Dunscombe, South Devon, was found and determined by the late C. J. A. 
-Meyer. An internal cast was collected from Bed 10 of Beer Head by Mr. Jukes- 
Browne, who also records the species from the Chloritic Marl of Maiden Bradley, 

' Fimbria coarctata, Zittel, ' Die Biv. d. Gosaugeb.,' pt. i (1864), p. 44, pi. vii, tig. 5. Kt-fonvd bv 
Stoliczka, aud subsecjueutly by Zittel aud by G. Miiller, to the genus MutielUi. Compare also the 
hiugeof Mutiella ruttindata figured by Guerauger, 'Album Pak'out. de la Sarthe' (1867), pi. xix, 
fig. 11. 



I'i2 CRETACEOUS LAMELTJBRAXCTTTA. 

and the Cliulk Mini of Chard. The specimens seen are nut sulHciently perfect for 
fiii^urinij. 

M. rotwudata is the type of the genus Matiella. In France this species is i'uiuid 
in the Cenomauian of Le Mans, Sarthe, Rouen, etc.^ 



i'^amiVy— UNICARDIID.E, Fisrh <,: 

Genus — Unicaedium, .1. iTOrhhjuij, 18i*,). 
(•rruilr. do Pill.,' vol. i, p. -218.) 

Unicakhhm ( laxciense, sp. nov. Plate XXV, figs. 7 a, l>. 

JJencriptiuii. — Sliell kxrge, oval, inflated, witli somewhat flattened sides, very 
inefjuilateral ; anterior jjart much longer than posterior part. Anterior margin 
WL']] rounded, passing gradually into the antei'O-dorsal margin, and into the ventral 
margin, which is only slightly curved. Posterior margin truncated. Umbones 
broad, curved inward and slightly forward. In front of the unil)ones the shell is 
dej)ressed . 

Ornamentation consists of narrow, sharp, prominent, somewhat irregular con- 
centric ribs separated by relatively broad, concave interspaces. 
Measurements : 

(1) (a) 

Length . . 52 . 40 mm. 

Height . . 45 . 34 „ 

(1, 2) Bfuuiwortla Haveu. 

Affinities. — In this species the umbones are not so high ami the posterior part 
of the shell is longer than in U. Iteterai'lifiim (d'Orbigny)- ; also the ril)s appear to 
be narrow and sharper. 

Type. — In the Sedgwick Museum, Cambridge. 

Distrihntion. — Claxl)y Ironstone (zone of llclciiniitc.s lutrrnlis) of Benniworth 
Haven, Lincolnshire. 



') 



' Corbis ? Morisoni, Woods, from the Chalk Rock of Cuckhamsley, is at present knowni by two 
iiuperfoct valves only. The hiuge cannot l)e seen, and the generic position of the species is still 
uucortain. See Woods, ' Quart. Journ. Geol. Soc.,' vol. liii, p. 392, pi. xxviii, figs. 13, 14. 

- In Murchison, de Verneuil and de Keyserliug, ' Gt'ol. Russie de I'Europe,' vol. ii (1845), p. 460, 
pi. xxxix, figs, n, 10. D'Orhiguy, ' Prodr. de Pal.,' vol. i (1840). p. 367. Eichwald, ' Lethiea Rossica,' 
vol. ii (1868), p. 647. Two examples of U. heteruclitum from the Lower Volgian, near Moscow, are in 
Mr. Lamplugh's collection. 



UNICARDIUM. 10:3 

Unicardium vectense, sp. nov. Plate. XXV, figs. 8—11. 

BcscripHon. — Shell thin, much inflated, oval or slightly subquadratc, inequi- 
lateral, the anterior part rather larger than the posterior part; length a little 
greater than height. Antero-dorsal margin short, nearly straight. Anterior 
margin rounded, making an obtuse angle with the antero-dorsal margin, and 
curving rapidly to join the moderately convex ventral margin. Posterior margin 
rounded, slightly truncated. Postero-dorsal margin slightly convex. Umbones 
prominent, contiguous, cur^ang inward and forwainl. Ornamentation consists of 
numerous, strong, somewhat irregular, concentric ribs. Ligament in a long, 
narrow groove. Teeth absent or poorly developed. 

Measurements : 

(1) (2) (;5) (4) 

Length . 20 . 18 . 10 . 12 mm. 

Height . 19 . 17 . 15 11-2 „ 

(1 — 4) Crackers, Atlierfiekl. 

Affinities. — The shell is relatively higher, the umbones more prominent, and 
the rilis rather stronger than in F. Ebra/ji, de Loriol.^ 

Distnbntion. — Lower Greensand: Crackers of Atherfield, Perna-hed of Sandown, 
and Ferruginous Sands of Shanklin. 



TJnicardium, sp. Plate XXV, fig. 12. 

A specimen of rnicardiitm Ironi the LTpper Greensand of South Devon- was 
collected by Sir H. T. De la Beche and is now in tlie Museum of the Geological 
Society, No. 1580. It resembles U. vectense, but the umbones are not so promi- 
nent and the ribs are .smaller, more numerous, and more regular. 



Uxii\\i;nirM ? oauitixim {Pii'td and Rovx), 1852. 

1852. CoRBLS GAULTiNA, F. J. Piclct anil W. Rout. Moll. Foss. Gris verts ilc 

Geneve, p. 448, pi. xxxiv, fif;. 4. 
1866. Fimbria — F. J. Pidet and G. Campiche. Foss. Terr. Crct. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), 
p. 282, pi. cxxii, figs. 3, 4. 
1871. — — F. Sfolirzl-a. Pala?out. Indica, Cret. Fauna S. Iiulia, 

vol. iii, p. 2.52. 
1875. CoRBis — A. J. Jidcs-Broicne. Quart. Jourii. Geol. Sec., vol. xxxi. 

p. 300. pi. XV, fig. 9. 



1 ' Gault de Cosnc' (1882), p. 70, pi. viii, figs. 13-16. 
- Probablv from near Siilinontli or Bluckdciwii. 



164 CEETACEOITS LAMELLIBRATsTHIA. 

Two internal casts from tlio C'amljridge Greensancl (derived from the Gault) 
were identified l)y Mr. Jukes-Browne as Cnrhis f/duUina, Pictet and Roux. Tlie 
specimens are in the Sedgwick Museum, and no other examples appear to have 
been Connd. The t.yp(> of ('. (/inilfiiia came from the Gault of Saxonot. In 
external I'nrm tliis species agrees closely with VmranVvim, hiif llic liiiige is 
unknown, so (lint the generic position cannot be determined with certainty. 



Unicakptum iMNriMEKiRNSE {MunlcII), 1822. Plate XXV, figs. 13, 14. 

1822. Venus? rinomekiensis, G. Mantell. Foss. S. Downs, p. 126. pl.xxv, fig. 5. 
18.50. Panop;ea — A. cVOrhujny. Prodr. do Pal., vol. ii, p. 1-57. 

IS.'J-t. Unicardium rinOtMERIENSE, J. Morris. Cat. Brit. Foss., cd. 2, p. 229. 
1865. Cardium — F.J. rirti'l find G.Campiehe. Foss. Terr. Cn't. 

Ste. Croi.v (Mater. Pal. Suisse, 
sor. 4), p. 195. 
Nou 1^50. Arca ringmerensis, II. B. Gcinitz. Das Quadorsandst. oder Kreidegeb. in 

Dentscliland, p. 162. 

— 1872. MuTiELi.A RiNOMERENRis. Tf. B. Gcinlt-.. Das Elbthalgeb. in Saclison (Pal- 

oeoutographica, vol. xx, pt. 2), 
p. 61, pi. xvi, figs. 11-13. 

— 1877. — — A. FrUfrh. Stud, im Gebiotc der bolini. Kroido- 

format. II Woisseuberg. w. Maluitz. 
Schicht., p. 115, fig. 75. 

— 1883. — — FriUcli. Ibid. Ill Iserschicht., p. 100, fig. 64. 

— 1889. — — Fritsch. Ibid. lY Teplitz. Schicht., p. 78. 

— 1807. — — Friiscli. Ibid. VI Chlomek. Schicht., p. 54, fig. 59. 

Descnj^tion. — Shell subquadrate, rounded, inflated, antero-dorsal part com- 
pressed, length rather greater thaji height, inequilateral, anterior j^art larger than 
the posterior part. Antero-dorsal margin nearly straight. Anterior margin 
moderately convex, making an obtuse angle with the antero-dorsal margin and 
curving rapidly near the ventral margin. The latter is moderately convex and 
curves upward to join the posterior margin, which is slightly cuiwed, and forms 
an obtuse angle witli the postero-dorsal margin. Umboncs large, ])roinin('Tit, 
contiguous, ciu'ving forward. Ornamentation consists of strong, narrow, con- 
centric ridfjes. 



Mcasnrevienfff : 








(1) 


(a) 


Length . 


42 


.■ICi nnu. 


TTeight . 


38 

(Ij Clialk Marl, Titherlcigh. 
(2) Chalk Marl, Chardstoek. 


■u „ 



THETIRONIA. 165 

Remarl's. — Tlie spt'ciniens from tlie Plant-r-kalk of Strelilen which were 
referred to this species by Geiiiitz appear to be related to Mutiella coarctata 
(Zittel).i 

Ti/pe. — The type came from the Chalk Marl of ]\liddleham, hnt cannot now be 
found. 

Distrihution . — Upper Greensand (zone of Schlmnharlna rostrata) of Devizes. 
Base of Chalk Marl of Titherlcigh and Chardstock. Chalk Marl of Middleham 
and Rino'mer. 



[Systematic position not determined.] 
Genus — TnETiKONiA, F. Stolicd-a, 1870. 

(' Palaeont. Indica, Cret. Fauna S. India,' vol. iii, p. 1-58. Thetis, J. do C. Sowerb_v, ' Min. Concli.,' 
vol. vi, 182G, p. 19. Non Thetis, Oken, 1815. Svn. Fimbnella, Stoliczka, op. cit., p. 24G.) 

The genns Thetironia \^T]ictis~\ has been placed in the family Vencridte by 
Deshayes, d'Orbigny, Chenn, Stoliczka, Zittel, Fischer, Dall, and other authors, on 
account of the presence of the acutely angular line which has often been regarded 
as a pallial sinus. This angular line appears as a deep groove on internal casts, 
and must consequently have been a prominent rib on the interior of the shell. In 
its position and rib-like form it is fpiite unlike the pallial sinus of any lamellibranch,- 
and it seems to be a structure of an entirely different nature, probably serving, as was 
suggested hj S. P. Woodward ^ merely to strengthen the thin shell. Thetironia is 
fui-ther distinguished from the VeneridtB by its hinge, which is of quite a different 
typo (see Plate XXVI, figs. 10/;, 14). Stoliczkii, in referring this genus to the 
Veneridae and sub-family Dosiniinfe, says : " There can be little doubt 
that all the external characters indicate a close appproach to the recent 
dementia " ; the hinge, however, which seems to have been unknown to Stoliczka, 
shows that this view of the relationship of Thetironia cannot be maintained. 

A concentric ridge seen near the ventral margin on some internal casts of 
Thetironia has been regarded by some authors as evidence of a simple jiallial line ; 
but the presence in some specimens of several similar ridges at different distances 
from the margin suggests that they are really of the nature of growth-rings (see 
Plate XXVI, fig. G). 

Thetironia was identified with Poromya by S. P. Woodward (1854) and by IT. 

1 G. Muller, 'Mollusk. Untersen. v. Braunschweig? u. Ilsede' (1808), p. GO. 

5 De Loriol compared it with Lucinopsis, hut the differences between the pallial sinus of that genus 
and the angular rib of Thetironia are consideiwble. 

s 'Manual of the Mollnsca," ed. 1 (18.M), p. 310; od. 3 (IS?.--.), p. 401. Woodward says. 
" umViones strengthened insiile by a posterior lamina. " 



ICG CRETACEOUS LAIHELLTBRAXCHIA. 

and A. Adams (lSr)R). Bosliayes (1858), and Pictet and Campiche (18G5), 
though considering tlieni allied forms, did not regard them as generically 
identical. The latter authors had little confidence in the suggested relationship of 
Thetironia to Venus, but in the absence of specimens furnishing decisive evidence 
they Jeft the former genus in the family Veneridag. In its external form and thin 
shell Thetironia shows some resemblance to Poromya, but the conspicuous internal 
ligament found in the latter is alisent in the former. 

In a systematic list of Mollusca, J. E. Gray ' placed Tkeiiroiti<i in the Lucinida?, 
but gave no reasons for assigning it to that family. Although elongate markings 
do occur in the interior of some species of Lncina, they show but little resemblance 
to the angular rib of TJicfironia. Fuither, the hinge is unlike that typical of Lucina ; 
for although in some icw species ('■. <j. L. ijiliha, L. pennsijloanica) in which the 
mnbones have a considerable anterior curvature, the positions of the cardinal teeth 
l)ecomc somewhat similar to those in Thetironia, yet this is clearly a secondary 
character due to torsion and cannot be taken as evidence of any affinity between 
Jjucina and TJietironia. 

The hinge in some of the Corbidfe, such as Sphxviola, Gonodon, and Miitiella 
resembles that of Thetironia, but is far stouter, and the shell is much thicker. The 
hinge in Utricardium also is somewhat similar to that of Thetironia, since lateral 
teeth are absent, but the cardinals are less developed. Unicardiiim, however, 
differs from Thetironia in the character of its ornamentation and in the form of 
the shell. 

In both form and position the teeth of TJietironia show a striking resemblance 
to the cardinal teeth of the Cardiid;i? (especially to Protocardia) , and the hinge- 
margin in front of the umbo expands in a similar way; some further resemblance 
is seen in the position and prominence of the external ligament, and in the general 
form of the shell, which is similar to that of the nearly smooth Cardium (Serripes) 
(jramJandicum, Chemnitz." The greater development of ornamentation on the 
posterior part than on the remainder of the shell in Thefirovia is also suggestive 
of some forms of Protocardia . The position of the cardinal teeth in the Cardiidas 
is practically constant and is a character of systematic importance ; so that the 
close resemblance between these teeth in Thetironia and in the Cardiidie seems to 
indicate a real relationship. Opposed to this, however, is the absence of lateral 
teeth ^ in Thetironia ; but although these teeth are usually found in the Cardiida?, 

1 ' Synopsis Brit. Mus.,' ed. 44 (1842), p. 91. 

- Although d'Orbigny placed Thetironia, in the Veneridae, he recognised that in some respects it 
clearly resembles Cardium. Sec ' Pal. Fran9. Terr. Crct.,' vol. iii (184t)), p. 4.'Jl. 

^ In the ' Additions and Corrections ' to his Monograph Stoliczka states that in Theiironia ignohilis 
there are two cardinals and a minute posterior lateral in the right valve, and tliivo cardinals in the 
left valve. ' Palieont. Indica, Cret. Fauna S. Indica " (1871), p. 48.'). 



THETIRONIA. 107 

yet they are occasionally al)sent. Otlici* differences arc seen in the very thin and 
punctate shell, and in the internal ril). 

Nothing closely resembling the internal rib of Thetironia seems to be known in 
any other laniellibranch. Bnt in some Jurassic and Cretaceous ^ species of Protn- 
airdia a rib, either single or A-shaped, is found at the inner Ijoundary of the 
posterior area ; this, however, differs from the rib of TJidironia, in that it reaches 
the margin of the valve and is not continued anteriorly to the neighbourhood of 
the anterior adductor. 

It seems, thei'efore, that although Thetirouia resembles the Cardiidic in several 
respects, yet the points of difference are too great to allow of its being included in 
that family. 

TiiETiiiDXiA JiiNuu (Suiceyhii), 1820. Plate XXV, figs. \oa—c; Plate XXVI, 

figs. 1—8. 

1822. Venus, G. Mantell. Foss. S. Downs, p. 73. 

1826. Thetis minor, /. de C. Soiverhtj. Min. ConcL., vol. vi, p. 21, pi. d.viii, 

fiys. 6 (? 5). 
1829. — —M.J. L. Beftance. Diet. Sci. Nat., v,.l. liv, p. 275. 

1841. — SowEEBii, F. A. Rijmcr. Die Versteiii. d. iiord-deutscli. Kreidugeb. 

p. 72 (jiartim). 
1845. — — var. a minor, var. /3. major. E. Forbes. Quart. Joiiru. 

Geol. Soc, vol. i, p. 242. 
184G. — L^viGATA, A. d'Orhi(jinj. Pal. Frauy. Terr. Crct., vol. iii, p. 452, 

pi. ccclxxxvii, figs. 1 — 3. 
1832-53. — MiNOE, G. P. Dcshaijcs. Traitii Elciueut. Conchyl., vol. i, p. 575, 

pi. xxii, figs. 3, 4. 
1854. — —J. Morrk. Cat. Brit. Foss., ed. 2, p. 227. 

— — — S. P. Woodward. Manual of the Mollusca, fig. 221 (on 

p. 318). 

1865. — —F.J. Pictet and G. Cavijjkhe. Foss. Terr. Crct. Ste. Croix 

(Mater. Pal. Suisse, scr. 4), 
p. 202, pi. cxii, fig. 4. 

1870. — LAEVIGATA, Pick'l uiul Cuiiqiiche. Iliid., p. 203, pi. cxii, figs. 2, 3. 

— Thetironia minob, F. StoUczha. PaliEont. Indica, Cret. Fauna S. luilia, 

vol. iii, p. 158. 
1884. Thetis hiinok, 0. Weertli. Die Fauna des Ncoc-oni. iin Teutoburg. Walde 

(FaUvout. Abhaudl., vol. ii), p. 41, pi. ix, 
figs, 5, 6. 
1898. — LiEViGATA, E. G. Skeat and V. Madsett. Jur. Neoc. and Gault 

Boidders in Deuiiiark, 
p. 176, pi. vi, figs. 7— 9. 



• Part of this rib is seen in a figure given by Pictet and Cainpiche, ' Terr. Cret. Ste. Croix ' 
("Mater. Pal. Suisse," ser. 4, 18GG), pi. cxxi, fig. 7a. 



168 CRETACEOUS LAMELLIIIP.ANCHIA. 

18y5. Thetis minok, F. Vorjel. Holliiudisch. Kreide, p. 58. 

I'JOO — — A. WoUemann. Die Biv. u. Gastrop. d. deutscb. u. bulliiud. 

Neocoms, p. 118. 

Nou 1846. — — A. d'Orhi(jiiij. Pal. Frau?. Terr. Crct., vol. iii, p. 4oo, pi. 

ceclxxxvii, fi^'s. 4 — 7. 

— 1850. — — d'Orh'ujiuj. Prodi-, de Pal., vol. ii, p. 136. 

— 1868. — — E. V. Eickwald. Letliaea Rossica, vol. ii, p. 707, pi. xxvi, 

fig. 6. 

iJescrijjtiuii. — Shell oval, ruiinded, convex, slightly (sonietimos moderately) 
inequilatei-al ; length rather greater than height. Margins forming nearly 
regular curves; anterior margin less convex than the posterior, making a ruundcd 
angle where it meets the nearly straight antero-dorsal margin. Umbones promi- 
nent, rather broad, close together, more or less curved forward. Lunular region 
depressed, not limited. Postero-dorsal region sometimes slightly compressed. 

Ornamentation consists of slightly-raised concentric lines at regular intervals 
with less distinct lines between ; and of regular rows of radial pits, whicli on the 
posterior part of the shell are replaced by rows of short spiny projections or 
minute tubercles. 

A long, acutely angular rib extends from the level of the posterior adductor 
to near the umbo. The front part of this rib is continued to near the anterior 
adductor, but is less prominent than the angular part ; at first it ciu'ves ventrally, 
and afterwards dorsally, the last part being somewhat angular. 

Measurements .- 

(3) (4) (5) (0) (7) (S) (9) (10) (11) 

27 20-5 25 23 30 20 20 17-5 17 iiim. 
25 25 24 21-5 27 23-5 18 i&b 16 „ 

(1 — C) Crackers, Atlierfield. 
(7 — 11) lutei'ual casts, Lower Greeusand, Shaukliu. 

Affinities. — Pictet and Campiche separated, but with considerable hesita- 
tion, the examples of Tketiroiiia found in the Crackers of Atliei'field from 
those found in the Ferruginous Rock of Shanklin. The former they referi'ed to 
T. laevigata, d'Orbigny (uo)i Sowerby) ; whilst the latter are tyi)ical of T. miiuir. 
There is, as stated by those authors, considerable difficulty in comparing 
specimens from the two localities owing to their different states of preserva- 
tion. Those from Atherfield have the sliell well presei'ved in nearly all 
cases, although not uncommonly the original form has been somewhat modified 
by crushing. The specimens from Shaukliu, on the other hand, are nearly always 
casts, but owing to the hardness of the rock they retain their original form 
more perfectly. 

Pictet and Campiche thought that the Atherfield form was less convex and 





(1) 


(2) 


Length 


31 


30 


Height 


28-5 


29 



TllETiKO.NlA. IG'J 

more inequiliitcral than the Shanklin form. After comparing a considerable number 
of specimens I find that those from Atherfield are, as a rule, slightly less convex ; 
but the more inequilateral character is not constant ; specimens of the same size 
are commonly quite as nearly equilateral, but the inequilateral character becomes 
more marked with age. Since larger forms are more common at Atherfield tlian 
at Shanklin, one may at first sight get the impression that there is a real difference 
in the iue(juilateral character. I have not seen any specimen iVum Atlierfield so 
inequilateral as the form figured by Pictet and Campielie appears to Ije, and I tliiid< 
it is probable that their specimen was somewhat distorted by crushing. 

T. geneceiisis, Pictet and Roux,^ is distinguished from T. minor by the heiglit and 
length being equal, b}' its more nearly equilateral form, and by a difference in the 
curvature of the rib in front of the angular part. 

BemarliS. — Thetlronia has been recorded by I'hillips and .ludd fi'oni the 
Speeton Clay, ])ut I have not seen any examples from tliat deposit. In some 
collections from Speeton specimens of Gijprlnci have been identified as Tlictironia. 

Type. — Fig. 6, Lower Greensand of Shanklin ; in the British Mu.seum. The 
original of fig. 5 from near Lj'me Regis has not been seen. 

Distribution. — Lower Greensand: Crackers of Atherfield; also recorded l)y 
Fitton from the Per;/ (t-bed and Beds vi, viii, ix, x, xiii, and xiv l)et\veen Ather- 
field and Blackgang Chine. Ferruginous Sands of Sliaidvlin. Atlierfield Beds of 
East Shalford. Hythe Beds of Hythe. Sandgate Beds of Sandgate, etc. Folke- 
stone Beds of Folkestone. 



Theiikonia l.kvi.;.vt.v {Sna-n-}„i), 1818. Phite XXVI, figs. 9—1-1. 

1818. CoRiiULA L.EViGATA, /. Soicvrhi/. Mill. CoUC'll., vul. ill, 1'. 1 I. [il. CL'ix, 

figs. 1, 2. 
182G. Thetis major, /. de C. Suirerhij. Ibid., vol. vi, p. 20, pi. dxiii, fif,'s. 1 — I. 
1829. — ~ M.J. L. Di/raiice. Diet. Sci. Nat., vol. liv, p. 27G. 

1850. Unicaedium ljevigatum, A. d'Orhignij. Prodr. de Pal., vol. ii, p. 1(33. 
1854. Thetis l.*:vigata, /. Morris. Cat. Brit. Foss., ed. 2, p. 227. 
— — MAJOR, Afurris. Ibid., cd. 2, p. 227. 

18(52. — — J. a. Cluiiii. Mauuel de Coiichyl., vol. ii, p. 90, fig. 405. 

18G5. — — F.J. Fictetaiul G. Citiiijilche. Foss. Terr. Cret. St t-. Croi.\ 

(Mater. Pal. Suisse, ser. 4), pp. 209, 
210, pi. cxii, fig. 5. 



1 Pictet aiid Rous, ' Moll. Foss. Grc-s verts de Geucve' (1852), p. 420, pi. xxx, fig. 2. Pictet and 
Campicbe, ' Terr. Cret. de Ste. Croix ' (18(55;, p. 20(5, pi. cxii, tig. 7. Barrois records T. (jciicvensis from 
the Upper Greeusaud of Lulwortb, but I have iiot seen any specimens ; see Barrois, ' Terr. Cret. Sujht. 
de I'Angleterre,' etc. (187G), p. 90. 



170 CRETACEOUS LAMELLIBRANCHIA. 

? 18U8. TuETis MAJuit, .1. Briarl and F. L. Curnel. Muulu de l>rac<|uei,'uii.'i5 (Mi'in. 

cour. et Mt'ui. des Sav. L'traugers, vol. 
xxxiv), p. 83, pi. vii, figs. 14, 15. 
1871. FiJiuiuELLA LJiviGATA, F. Stol icxJcti. Palicout. Iiidica, Cret. Fauua S. 

ludia, Vol. iii, p. 24G. 
1882. Thetis majob, P. de Loriol. Gault de Cosue, p. (Jl, {A. viii, figs. 6 — 8. 
rl874. — — W. Daiiu'g. Zeitschr. d. deutsdi. geol. Gesellscb., vol xxvi, 

p. 7(3(3, pi. xxi, fig. 4. 
1885. — — F. Nutlinij. Die Fauna d. baltiscli. Ceuomau. (Palscout. 

Abliaudl., vol. ii), p. 2'J, pi. v, fig. (3. 

Non 1845. — Sowerbii var. li majuk, E. Furbcs. Quart. Joiu-u. Geol. Soc, vol. i, 

p. 242. 

— 1846. — majok, ^1. d'Orhlijiiy. Pal. Frauc,'. Terr. Cn't., vol. iii, p. 454, vol. 

ccclxxxvii, figs. 8 — 10. 

— — — LasviGATA, d'Orbiijni/. Ibid., vol. iii, p. 452, pi. ccclxxxvii, figs. 1 — 3. 

— 1850. — — d'Orblymj. Prodr. de Pal, vol. ii, p. 118. 

— — — MAJOR, d'Orhhjnij. Ibid., vol. ii, p. 160. 

V — 1852. — SowERBYi, ii'. JiHtr. Deuksclir. d. k. Akad. Wissenscli. Wieii, Math.- 

uat. CI., vol. iii, p. 311, pi. xvi, fig. 21. 
'i — 1868. — MAJOK, E. V. Eichwald. Letha;a Kossica, vol. ii, p. 708. 

Mi'iisiircmciitft : 

(1) (L-) (:!) (.1.) (5) ((!) 

Length . 47 -1-2 -11 o9 30-5 29-5 
Ht'iglit . 43 40 39 37 27 28 

(1—10 Blackdowu. 

Ajjinitirs. — This species is closely allied to 1\ minor, with which it was uiiitcil 
liy ll(")iiiei- under the name T. Soiccrlni, but it possesses relatively higher and 
narrower uniljones than T. minor. T. laivijata is commonly of larger size than 
T. mJiKir, and as in the case of the latter, the large forms are more inequilateral 
than the small I'urms. A ratlier small example was figured by Sowerby as ('orlmhi 
Iciivvjiilii, ami Avas taken l)y Stoliczka as the type of a new genus Fimbriella, but it 
pi'oves to be, as was suggested by Pictet and Cam])iche, an example of 1\ viajur. 

The hinge can be seen in some specimens from Blackdown (Plate XXVI, figs. 
19 A, 14). It consists of two small conical or tubercular teeth just below the 
umbo of each valve. In the right valve the teeth are placed one above the other, 
but the dorsal tooth is slightly in front uF the ventral and rather smaller than the 
latter. In the left valve the teetli are side by side, nearly on the same level, 
and the anterior tooth is rather larger than the posterior. Lateral teeth are 
absent. The external ligament is short and prominent. 

Ti/pes. — The type of ('orhula ln'chjata, from Blackdown, and the types of 
Thetis major, from Blackdown and Devizes, are in the British Museum. T. major 
is the type of the genus Thetis, tSowerb}-. 



(7) 


(S) 


(■J) 


22-5 


22 


13 mm. 


21 


22 


13 „ 



TELLINA. 171 

Distrihiifioii.—GAv\\t of Black Ven. Upper Greensand (zone of Schlocnhachia 

rostrata) of Blackdown, Potternc, Devizes, and near Lyme Hegis. Recorded by 
Price from tlie Gault of Folkestone. 



i^.n/;////— TELLINIDyE, Dcshai/rp. 
Genus — Tellina, TAnnxu^. 

(•Syst. Nat,,' eel. 10, 1758, p. C74 ; e.l. 12. 1707, p. lUG.) 

Teli.ix.v Carteront, ,rOrhhnui, 1S45. Plate XXVI, figs. 1-"), IG. 

1842. Tellina ? vel Psammobia ? angulata, Deshayes in A. Leymerie. Mem. Soc. 

geol. de Prance, vol. v, pp. 3, 24, 
pi. iii, fig. 6 (uon T. amjulata, L.). 
1845. — ANGULATA ?, E. Forhes. Quart. Journ. Geol. Soc, vol. i, p. 239. 

— Tellina Carteroni, A. d'Orhiijmj. Pal. Franc. Terr. Crcl., vol. iii, p. 420, 

pi. ccclxxx, figs. 1, 2. 
1850. — — (VOrhujny. Prodr. de Pal., vol. ii, p. 75. 

18(31. — — p. (7e Loriol. Anini. Invert. Foss. Mt. Salcve, p. 5i), 

pi. vii, fig. 2. 
1865. — —F.J. Field and G. Campiche. Foss. Terr. CrJt. Ste. 

Croix (Mater. Pal. Suisse, ser. 
4), p. 134. 
1870. — — F. StoUrxlca. Palocout. ludiea, Cret. Fauna S. India, 

vol. iii, p. 123. 
1884. — — 0. Weertli. Die Fauna des Neocom. im Teutoburg. 

Walde (Pala;ont. Abhandl., vol. ii), 
p. 41. 
1895. — — Cf, Maas. Zcitsclir. d. deutscli. gool. Gesellsch., vol. 

xlvii, p. 257. 
1900. — — A. Wollcmann. Die Biv. u. Gastrop. d. doutsch. n. 

lioUiind. Neoconis, p. 121. 

Descriplion. — Shell elongate, much compressed, inequilateral, length equal to 
more than twice the height. Anterior margin rounded, curving rapidly to join 
the slightly curved ventral margin. Posterior margin oblique, forming an angle 
with the ventral margin, A shallow furrow passes from the umbo to the middle 
of the ventral margin. ITmbones small, curved forward. A .sharp carina extends 
in a curve from the umbo to the postero-ventral angle, and cuts off a narrow, 
flattened, postero-doi'sal area. Ornamentation con.sists of fine radial ribs on the 
anterior and ])o.<:terior parts of the valves, especially just in front of the carina ; 
growth-lines distinct. 



172 CRETACEOUS LAMELLTBRANCHIA. 

Measurements : 

(1) (2) (3) (1) 

Length 39-2 . 39 . 38 . 30 mm. 

Height 17 . 10 . 10-5 . 15-2 ., 



"D 



(1 — 4) Crackers, Atherfield. 



Affinities. — The English specimens differ from the figure of T. Carteroni given 
l)y d'Orbigny in the greater curvature of the carina, the narrower postero-dorsal 
area, and the greater upward bend of the anterior end of the shell. Professor 
T3oule has kindl}- examined the specimen figured by d'Orbigny, and states that 
the carina is more curved and the postero-dorsal area narrower than represented 
in the figure ; also the anterior part has been restored. Professor Boule has also 
compared a photograph of a specimen fi-om Atherfield with d'Orbignj^'s specimen 
and considers that they do not differ specifically. Pictet and Campiche w'ere able 
to compare English with French specimens, and the principal difference which they 
noted was the occurrence of fine radial ribs on the ]iosterior part of the shell in 
English specimens; but I find that those ribs are indistinct or absent in specimens 
which are not quite perfectly preserved. 

The figure of T. angnlata given by Deshayes appears to differ from 7'. ('iirtryinii 
in its more elongate form and the greater length of the anterior region, but these 
differences are probal:)l3' due to the imperfection of the specimen. Previous writers 
have not regarded it as distinct from d'Orbigny's T. Garteroni. 

Stoliczka regarded T. Garteroni as a typical Tellina. It resembles closely the 
sub-genus Phijllodn, Schumacher. 

One specimen fi'om Atherfield (Plate XXVI, fig. 17) differs from the other 
examples of this species in the occurrence of strong radial ril)s on the posterior 
part of the shell. It may be only a variety of T. Garteroni. 

Tij2)e. — From the Neocomian of Vendeuvre ; the original cannot be found. The 
specimen figured by d'Orbigny came from Marolles. 

Distribution. — Lower Greensand (Crackers) of Atherfield. Atherfield Beds 
of East Shalford. 



TEf.r.iXA sTR r ATI- 1.01 m-.s, Stolirzht, 1870. Plato XXVI, figs. 18, 19; Plate XXVII, 

fig. 1 . 

1824. Tellina stuiatula, J. de C. Sowerhy. Min. Condi., vol. v, p. 70, jil. cccclvi, 

fig. 1 (iKiu T. atriiitidd. Olivi, 
Pxiltoii, Lainarck). 

1850. — —A. d'Orhlij,,;/. rrodr. di- Pal, vol. ii, p. l.W. 

1854. — — J. Morris. Cat. Brit. Foss., ed. 2, p. 226. 



TELLINA. 173 

1865. Tkllina stuiatula, F. J. Pictet and G. Campiche. Poss. Terr. Crct. Ste. 

Croix (Miiti'r. Pal. Suisse, ser. 
4), p. IS'J. 
1870. — (TELLiNELhA) sTRiATVLOiDES, F.Stoliczka. Palaeout. Indica, Cret. 

Fauna S. India, vol. 
iii, p. 123. 

Descrijjfion.^tiheW elongate-oval, compressed, inequilateral; length equal to 
about twice the height ; the anterior part longer than the posterior part. Anterior 
margin rounded. Ventral margin slightly curved, making an angle with the 
posterior mai'gin. Posterior margin oblique, curved near the postero- ventral 
angle, and forming an obtuse angle with the postero-dorsal margin. Unibones 
inconspicuous, only slightly curved. A rounded carina extends in a nearly straight 
line from the umbo to the postero-vcntral angle, and cuts off a flattened postero- 
dorsal area. Ornamentation consists of small radial ribs on the postero-dorsal area 
and ou the part just in front of the carina ; also on a small part of the shell near 
the anterior margin. Fine concentric lines are also present, and are more 
distinct on the anterior and posterior parts of the shell than elsewhere. Pallial 
sinus relatively small, somewhat angular. 

Measurements : 

(1) (2) 

Length . 30 . 27 Jum. 
Height . 14-6 . 13-2 „ 

(1—2) Blackdowu. 

Affinities. — Stoliczka placed this species in the sub-genus Tellinellu, witli which 
it agrees closely in external form, but the ol)li(pie cardinal teeth resemble more 
closely these of the sub-genus I'aliwvurra. 

Tijije. — From Blackdowu ; in the British Museum. 

Bistrihutiun. — Upper Greensand (zone of Schlanihachia rostrata) of Blackduwu 
and Haldon. Recorded by Jukes-Browne from the higher part of the zone of 
Pecten aspcr in North Dorset. 



Section — P.\l.eomu;i{a, F. Stoliczka, 1870. 

('Palaeont. ludica, Cret. Fauna S. India,' vol. iii, p. IIC.) 

Tellina (PALjiOM(ERA) iN/EQUALis, Soiverbij, 1824. Plate XXVII, figs. 2—8. 

1824.. Tellina in.kqualis, J. de C. Sowerhij. Min. Conch., vol. v. |). 80. pi. 

ccc-clvi, fij^. 2. 
1850. Aecopaoia — A.d'Orbigny. Prodr. de Pal, vol. ii, p. 158 (^»ar/im). 

1854. Tellina — J. Morris. Cat. Brit. Foss., ed. 2, p. 226. 

23 



\7l CRETACEOUS LAMELLIBRANCIIIA. 

y IStJy. Tellina iNj;<iUA.Lis, A. Biiaii and F. L. Conwt. Mculu de lii-acqufguies 

(Miin. cour. et Mc'iii. des Sav. 
ctrangers, vol. xxxiv), j). 77, pi. 
viii, figs. 24, 25. 
1870. Abcoi'agia — (Lineaeia), F. Stoliczka. Palaeont. ludica, Cret. 

Fauna S. India, vol. 
iii, p. 124. 
Nou lb4.5. Tellina — 't', E. Forbes. Quart. Jouru. Geol. Soc, vol. i, p. 2'3'J. 

Descrqifiov. — Shell oval, moderately inequilateral ; length rather more than 
1^ times thf height; left valve less convex than the right. Anterior part of 
valve.s rounded. Posterior margin convex, subtruncate, more or less ob]i(|ue, 
forming a blunt angle with the ventral margin. A slight carina extends from the 
umbo to the postero-ventral angle and cuts off a flattened postero-dorsal area. 
Umbones moderately prominent. I'allial sinus large, rounded. Postero-dorsal 
area ornamented with small radial ribs; the remainder of the shell smooth 
except for growth-lines. 



Measurements : 
















(1) 


(2) 


(3) 


(i) 


(5) 


(0) 


Length 


29 . 


28 . 


27 


. 2G . 


23-5 , 


. 18 mm 


Height 


18-5 . 


18 . 


17 


. 16-5 . 


14-5 


. 11 „ 


Thickness . 


9 . 


7-5. 


8 


. 7-25 . 


()-5 


?J 



(1—6) BlaekdoAvii. 

Aj]iiiiti<'H. — T. slriijata Goldfuss,^ from the Aachen Greensand, is simihir in 
form to T. iiueijunlix, but possesses fine radial ornamentation over the entire surface 
of the shell. T. liui/imti, d'Orbigny,- is also similar in form, but appears to be more 
nearly ecpiilateral and without radial ribs. 

A species of TcUimt found in the ]\leule de Hracquegnies was referred to 
T. iiueqiniJis by Briart and Cornet, but it appears to differ in some respects fi'om 
the latter. The specimens which I have seen from Bracquegnies are not 
sufficiently well preserved to enable me to express a defiuito opinion as to their 
relationship to T. insequalis. 

Ti/pc—Vvoni the Upper Greensand of IJlackdou n ; in the British Museum. 

Distrlbnliua. — Upper Greensand (zone of SchlanbacJiin nislniln) of Blackdown 
and Ilaldon. Recorded by Jukes-Browne from the Upper Greensand of Devizes 
and the Isle of Wio-ht. 



'O' 



' ' Petrel'. Genu.,' vol. ii (1840), p. 234, pi. cxlvii, ii^-. 18. Holzapi'el, 'Die MoUusk. Aachen. 
Kreide ' (PaloGoutograpliica, vol. xxxv, 1889), p. 159, pi. xi, figs. G-10. Tliis species is the type i^ii' the 
sub-geuus or section Puhvmcera, Stolie/.ka, 1870. 

2 'Pal. Frauy. Terr. CrJt.,' vol. iii (1845), p. 422, pi. lclI.x.x-x, tigs. 0-11. 



TELLINA. ] 75 



Svh-f}eiiv.<i — LiNEAKiA, T. A. Covrad, 18G0. 

(' Jouni. Acad. Nat. Sci. PliiLnl.,' scr. 2, vol. iv, p. 270, ami ' Amer. Joiirn. Conch.,' vol. vi 

[1870], p. 73.) 

Ti.;tj,i\a (Lineatjia), sp. Plate XXVII, fig. 9. 

J)escriptioii. — Shell oval, moderately convex witli tiattcned sides, nearly 
equilateral. Anterior margin ronnded. Ventral margin slightly convex. Posterior 
margin slightly truncated, rounded. Umbones inconspicuous. Postero-dorsal 
region slightly compressed, but not limited by a carina. 

Ornamentation consists of numerous, strong, regular, concentric rilis separated 
by narrow grooves ; and a few small radial ribs on the anterior and posterior 
parts, those on the latter sometimes not reaching the margin. Length lG"o mm.; 
height 10-5 mm. 

Affinities. — This species, of which only a few examples have been seen, is 
closely allied to, if not identical with, T. Baulinimia (d'Orbigny),^ but the posterior 
ribs are less prominent. The shell is less elongate than is d'Orbigny's type, Ijut 
scarcely differs in this respect from the example figured by Pictet and Campiche. It 
is more elongate and has the postero-dorsal region less flattened than in 
T. ftubconcentricn (d'Orbigny)." T. ftuhhrrcijvira, Maas, is another similar form. 

Distribution. — Lower Greensand (Crackers) of Atherfield. Atherfield Beds of 
East Shalford.^ 



Tkt.uxa (Lixearta) .sudtenuistkiata, iVOrhiijny, 1850. Plate XXVII, figs. 10 — 13. 

1836. Amphidesma ? tenttistriatum, /. (h C. Sowerhy. Trans. Geol. Soc., ser. 2, 

vol. iv, pp. 230, 341, 
pi. xvi, fig. 7. 
1850. Teli.ina subtenuistriata, A. iVOrhigiiy. Prorlr. dc Pal., vol. ii, p. 150 

(nou T.tennisiriata, Desliayes, 
1824). 
1854. Amphidesma ? tenuisteiatum, J. Morris. Cat. Brit. Foss., cd. 2, p. 183. 



1 For references see p. 176, footnotes 1 and 2. 

- Some specimens from the Folkestone Beds of Folkestone agree in form witli T. xvhconcenlrica, 
hut owin<i to the imperfect preservation of the surface the character of the ornamentation cannot be 
made out satisfactorily. 

3 It is possible that TeUina xqunlig, Mantell {iiom. nu(l.), from the Lower Greensand of rarham, 
mav 1)1' the form described above. Mantell, ' Tran.-;. Geol. Soc..' ser. 2, vol. iii (1820), p. 211. 



17G CRETACEOUS J.AMELLIBRANCHIA. 

1865. Tellina subtenuistriata, F. J. Pidcl and G. Campiche. Foss. Terr. Crit. 

Ste. Croix (Mater. Pal. 
Suisse, ser. 4), pp. 132, 
138. 
1870. Amphidesma tenuistbiatum, F. Stoliczka. Palaeont. InJica, Cret. Fauna 

S. India, vol. iii, p. Ill 
{?Thracia or Tellina). 

Description. — Shell oval, of moderate convexity, nearly equilateral. Anterior 
margin rounded ; ventral margin moderately convex ; posterior margin truncated, 
more or less oblique, forming a blunt angle with the ventral margin, and an obtuse 
angle with the postero-dorsal margin. Umbones rather liroad, scarcely curved. 
Postero-dorsal part of shell compressed and flattened. 

Ornamentation consists of numerous strong, regular, concentric ribs, and of a 
few small radial ril)s on the anterior pai-t, and of a larger number on the postero- 
dorsal region and the part just in front of it. 

Measurements : 

(1) (2) (3) (1) 

Length . 19 . 18 . 17 . 1:5 nun. 

Height . 13-5 . 13 . 11-5 . 9 „ 

(1 — 4) Blackdown. 

AlJiiiities. — This species resembles Tellina Ihmllniana (d'Orbigny),' but possesses 
a relatively shorter and liigher shell, with a more convex ventral margin and more 
numerous radial ribs. In form it approaches more nearly the examples from the 
Gault of the Pertc du Rhone figm^ed by Pictet and Campiche,- but in the latter 
the posterior extremity is more angular and the posterior riljs more prominent and 
limited to the postero-dorsal region. 

T. subtenuistriata also resembles T. subconcentrica (d'Orbigny),^ l)ut is more 
nearly equilateral and the ventral border is more convex. 

It differs from the species from the Lower Greensand described above in the 
flattened postero-dorsal region, the more angular posterior extremity, the smaller 
a[)ical angle, the larger curvature of the ventral margin, and greater relative 
height. 1\ siibhercynica, Maas,* is another similar form. 

Bemarhs. — The type is somewhat imperfectly preserved, but the radial ribs on 
the anterior and posterior parts, which are not shown in Sowerby's figure, can be 
made out satisfactorily. The size of the apical angle and the outline of the shell 
vary in different examples. 

1 ' Pal. Franv. Terr. Crct.,' vol. iii (1845), p. 411, pi. ccckxviii, figs. 7-10. 
- Pictet and Campiche, ' Terr. Cret. Ste. Croix ' (1865), p. 141, pi. cix, figs. 1-3. 
■' Op. cit., p. 410, pi. ccclxxviii, figs. 1-C, and ' Prodr. de Pal.,' vol. iii (1850), p. 75. Pictet and 
Renevier, ' Foss. Terr. Aptien' (Mati'r. Pal. Suisse, ser. 1, 1856), p. 69, pi. vii, fig. 7. 
' 'Zeitschr. dcr deutscb. geol. Gesellscli.,' vol. xlvii (1895), p. 258, pi. vi, figs. 3, 4. 



MACTRA. 177 

Type. — From Blackdown ; in tlie Bristol Museuin. 

Distribution. — Upper Greensand (zone of Schlamhachia rostrata) of Blackdown. 

Tellina (Lineaeia) sp. Plate XXVII, figs. 14— IG. 

Beseription. — Shell oval, moderately convex, with flattened sides, nearly equi- 
lateral. Anterior and posterior margins rounded. Ventral margin only slightly 
curved, and nearly parallel with the dorsal margin. Umbones broad, nearly median. 
Postero-dorsal part of valve flattened, rather large, limited by a faint carina. 

Ornamentation consists of numerous small, regular, concentric ribs, and 
numerous small radial ribs on the postero-dorsal area and near the anterior end. 

Measurements : 

(1) (2) (3) 

Length 17 . 15 . 14 mm. 

Height . 12 . 10 . 9-5 „ 

(1—3) Blackdown. 
Affinities. — This species resembles T. BauUniana (d'Orbigny), Ijut tlie radi:il 
ribs are much more numerous. It is also similar to the form from the Lower 
Greensand described above, and to T. .•<iil>h<')ri/iiica,'Maas. 

Distrihnfinu. — Upper Greensand (zone of Schlcenbachia rostrata) of Blackdown. 



i^aJHi/y— MACTRID^, Clra>/. 

Genus — Mactra, Linnseus, 1 7Cu. 
(' Syst. Nat.,' ed. 12, vol. i, p. 1125.) 

Mactba, sp. Plate XXVII, figs. 17, 18. 

A few specimens which rescml)le Mnctra extcrnallv, but of which the hinge has 
not been seen, were found in the Lower Greensand (Ferruginous Sands) of Shank- 
lin by the late C. J. A. Meyer. They are rather larger and relatively higher than 
M. (UKjulatti, and the carina is less distinct. The surface of the shell is ornamented 
with small concentric ribs. 

Mactra angulata, Sowerhy, 1830. Plate XXVII, figs. 19—23. 

1836. Mactea ? ANGULATA, J. dc C. Sowerhy. Tran.s. Gcol. Soc, ser. 2, vol. iv. 

]>]>. 241, 341. pi. xvi, fig. 9. 
1850. Mactea anoulat*, A. (VOrhi(ji)y. Prodr. do Pal., vol. ii, p. 158. 



178 CRETACEOUS LAMELLIBRANCHIA. 

1854. Mactra anoulata, /. Morris. Cat. Brit. Foss., eil. 2, p. 2U9. 

18(35. — — F. J. Bidet and G. Campiche. Foss. Terr. Crut. Ste. 

Croix (Mater. Pal. 

Suisse, sor. 4), p. 120. 
1870. — — F. StoUczka. Falseont. Imlica, Cret. Fauna S. ludia, 

vol. iii, pp. 55, 56. 

Non 1851. — — J. MiiUi'r. Petref. dcr Aaclien. Kreidef., pt. 2, p. 66 

(= M". Bosquetiana, Stoliezka). 

— lOOl. — — F. Sturm. Jaliili. <1. k. prcuss. fjeol. Landesanst. fiir. 

r.»L)U, vol. xxi, p. 84, pi. viii, fit;. 1. 

Description. — Shell small, convex, Rul)triangiilar, slightly incquilatoral, with 
the antero- and |)ostero-dorsal parts bending raj)idly to the margins. Antero- 
dorsal margin long. Anterior margin ronnded. Ventral margin convex, forming 
an angle with the posterior margin, which is trnncated, oblique, and slightly convex. 
Umbones prominent, pointed, curved inwards, with a carina which extends in a 
gentle curve to the postero-ventral angle. Ornamentation consists of fine con- 
centric ribs, wliifli l)i'coni(' fewer and stronger near llie antero-(loi-s;d and posfcro- 



dorsal marcfin. 




Mpdsurcmpufii : 






(1) 


Length 


14 


Height 


12 



(2) (3) (4) 

13 . 10 . 8 mm. 

10-5 . 8 . 7 „ 

(1 — 4) Blackdovm. 

Affinities. — In form and ornamentation M. nuijiilKfn resembles M. Warrrnana, 
Meek and llayden,^ but the latter is of larger size and the umbones show a distinct 
anterior curvature. 

A species found in the Aachen Grecnsand, now known as if. Bosquetiana, 
Stoliezka, was identified with M. nnr/nJata by Midler, but is distinguished from 
I he latter, as Stoliezka pointed out, by its greater length, smaller convexity, rotinded 
posterior margin, and other characters. 

Ti/jje. — From Blackdown ; in the Bristol Museum. 

l^istrihntion. — Upper Greensand (zone of Selihvnhachia rostra t a) of Blackdown 
and Ilaldon. Recorded by Barrois from the Upper Greensand of Tjulworth and 
by Jidces-Brownc from the equivalent of the Blackdown Beds at Sidmouth. 

1 Meek, 'Invert. Cret. and Tort. Foss. U. Missouri ' (187(i). P- 208, pi. xxx, fig. 7. Wliiteaves, 
' Mesozoic Foss.' (aeol. Surv. Canada), vol. i (187;>), p. 142, pi. xvii, fig. 9, pi. xix. fig. 3. 



[■TVL'liUMVA. I7<j 



iJciuLH — Ptvuiidmva, L. Jfjii.sai::, JSL'J. 
(• Etudos crit. Mull, i'oss.' ; Mjus, p. xviii, pi. .vi, ligs. ;), 1-.) 

Ptychomya Rouix.vi,iii\A {irOrblijuij), 18-^1.1-. i'late XXVII, figs. 24—20. 

1842-45. Ptychomya plana, L. Ajtcy^iz. J'Jtuilos crit. Moll. Foss. ; Myes, p. xviii 

(1845), pi. xi, fii,'s. 3, 4 (1842). 

1844. Ckassatella kuuinaluina, ^1. tVOrbiijinj. Tal. Frau^. Terr. Crt't., vol. iii, 

p. 75, pi. cclxiv, figs. 10 — 13. 

1845. — — E. Foi-hi-s. Quart. Jouni. Geol. Soc, vol. i, 

p. 241. 
1850. — — d'OrhifjMj. Prodr. de Pal., vol. ii, p. 77. 

1854. — — /. MurrU. Cat. Brit. Fuss., ed. 2, p. 19(3. 

1855. — — G. Cotlcaii. Mull. Fuss, de I'Youue, p. 71. 
180(J. Ptychomya — F. J. Fidel and (V. Cainpichc. Foss. TeiT. Crt't. 

Ste. Croix (MatiT. Pal. Suisse, 
ser. 4), p. 352, pi. cxxvii, 
figs. 2— (i. 
18(J9. IvAUlocoNCHA — T. A. Conrad. Aiiier. Juuru. Couch., vol. v, 

p. 47. 

Dr>icrq)lioii. — SliL'll uval-o!)luiiii-, fluiigate, convex, but with Hattoucd sides, very 
iue(|iiilaterul, anterior part rather higher than the posterior part. Anterior 
margin regularly rounded. Ventral margin oidy slightly curved, nearly parallel 
to the dorsal margin. Posterior margin oblique, forming an acute angle w ilh the 
ventral margin and an obtuse angle with the slightly curved postero-dorsal margin. 
Umboues inconspicuous. On the postero-dorsal sitle of a line from the umbone to 
the posterior extremity the shell is flattened. Lunule narrow, elongate. 

Ornameutatiou consists of strong radial ril)s, which are .sometimes more or less 
nodose. Those on the pu.sterior part uf the shell are stronger and separated by 
broader furrows than those on the anterior part. The ribs which reach the 
posterior margin start from the timbo ; the others start from a line between the 
umbo and a point on the opposite margin which is about a quarter of the distance 
from the anterior to the posterior end. In front of this line the ribs form a 
considerable curve ; behind it they are only slightly curved; the ribs meet at an 
acute angle at the line mentioned Forming either a A throughout or a chevron M, 
on the ventral part. The postero-dor.sd margin is ornamented with strong nodose 
ridges. 



180 ("KE'rACEOUS L \:\!ELLIliRANCHIA. 

Mea^-uremeids .- 

(1) (2) (3) 

Length . 80 . 70 . 69 ram. 
Height . 44 . 39 . 36 „ 

(1 — 3), Perna-hed, Atherfield. 

Afjlnities. — Forl)es states that English examples of this species were identified 
bv comparison with French specimens. I have not seen any foreign examples of 
P. Uohhidhlina, but the English specimens appear to differ from those fignred by 
(r()il)igny and by Pictet and Campiche in their greater convexity and larger size, 
in the more acnte angle wliieli the ribs make at the dorso-ventral line, and in the 
somewhat less anterior position of that line. In all these respects the English 
examples approach more nearly to /'. iieoromiensk (de Loriol),' bnt differ from that 
species in their more elongate form. It seems, however, not nnlikely that a large 
nnmber of specimens might show that 1\ liohinaldina and /'. ii/'ocomicnsh are not 
specifically distinct. In connection with this, attention may ])e called to Nnctthi 
(Acila) bivirgafa, Sowerby, in which the ornamentation is somewhat similar and 
shows considerable variation. 

The genus Pti/chomi/a was placed in the Crassatellitida^ by Pictet and Cam])iche 
and by Stoliczka. Its resemblance to Circe (Criifa) was pointed out and fully 
discussed by Dames," whose view of its systematic position is accepted by Fischer. 

Remarks. — The date of the plate on which Agassiz figured rti/chomya plana is 
earlier, but the text relating to it is later than d'Orbigny's figure and description 
of Grassatella Rohinaldina. Since the specimen figured by Agassiz is rather 
unsatisfactory and d'Orbigny's name has been used by nearly all writers it seems 
desirable to retain the latter. 

Dkirihntion. — Lower Greensand (/Vr;irt-bed) of Atherfield. Ferruginous 
Sands of Shanklin. Hythe Beds of Hythe, Lympne, and Maidstone. 

1 Pictet ami Campiche, "Terr. Crct. Ste. Croix" ('Mater. Tal. Suisse,' ser. 4, 18(JG), p. 855, 
pi. cxxvii, fi<fs. 9 — 12. 

- ' Zeitscbr. d. dcutscL. geol. Gesellscli.,' vol. xxv (1873), p. 374', i)l. xii, figs. 1 — 4. 



Ipalcxontoorapbical Socict\>, 1908. 



A M()X()(; RAPH 



OF THE 



CRETACEOUS LAMELLIBliANCHL^ 



ENGLAND. 



HENRY WOODS. M.A. 

DNIVERSITT LECTUREE IN PAL.BOZOOLOUT, CAMBRIDOE. 



VOL. IL PART V. 

VENERID.E, CARDIID.E, DICER ATID.E, MONOrLEURID/E, AND 

CORBULID.E. 

Pages 181—216; Plates XXVIII— XXXIV. 



L O .\ D O N : 
PRINTED FOR THE PAL^ONTOG RA l" HI A L .SOCIETY. 

1908. 



BBIKTED BY ADLAKD AND SON, LONDON AND DORKING. 



l)()SIN10l'SJ8. iyl 



(Innis — DdsiNlor.sis, T. .1. ('(iiiniJ, IHlJI. 
(' I'roc. Acad. Nat. Sci. Pliila-ai-lpliia,' |). -JllJ.) 



DoSINIOl'SIS SUliEOTUNl>.\ {Soirrrhlj), 1 830. I'latu XXVIII, lig.S. 1 — (J. 

1836. Cythkb«a subkotunda, ,/. de C. Sowerby. Trans. Geol. Soc, ser. 2, vol. iv, 

pp. 240, :3-il, pi. xvii, tig. 2. 
1850. Venus — A. cVOrhUjnij. Prodr. de Pal., vu\. ii, p. 159. 

1854. Cythkkea — J. Morris. Cat. Biit. Foss., ed. 2, p. 201. 

1870. Venu.s — /*'. Sluliczka. Paleeout. ludica, Cret. Fauua S. 

India, vol. iii, p. 161 (Caryalis). 

Description. — Shell rather thick, rounded, oval or somewhat orbicular, of small 
or moderate convexity ; length rather greater than height ; moderately, sometimes 
considerably, inequilateral. Antero-dorsal margin long, concave. Anterior 
margin rounded, passing gradually into the considerably curved ventral margin. 
Postero-dorsal margin very long, convex, witli a considerable ventral slope. 
Posterior margin rounded. Umbones small, pointed, close together, slightly 
curved anteriorly. Lunule elongate, depressed, distinctly limited. Escutcheon 
narrow, depressed, with a sharp border. Pallial sinus rather large, sub-angular. 
Ornamentation consists of fine concentric striae, and growth-lines. 

Hinge : In the right valve three strong, nearly straight, diverging cardinal 
teeth, of which the anterior and median are closer together and diverge at a 
smaller angle than the median and posterior, the last being divided l)y a shallow 
longitudinal groove; there is a small posterior lateral tooth and an elongate 
anterior pit. In the left valve the anterior of the three diverging cardinal teeth is 
nearly vertical, the median is the stoutest, and the posterior is oblicjue and slender ; 
the anterior lateral tooth is elongate and pai'allel to the lunular margin; the 
posterior lateral is very small. 
Measure 1)1 cuts .- 

(1) (2) (y) (t) (5) 

Length . 34 . 31 . 2\) . 28 . 20 mm. 

Height . 32 . 28 . 20-5 . 20 . 2:3-5 „ 

(1 — 5j Blackdowu. 
Ti/pe. — From Blackdowu; in the Bristol Museum. 
Distribnilon. — Upper Greensand (zone of Srlduiubuchia ro.slndu) of Blackdown. 



24 



182 CRETACEOUS l.AMELLIIiliANCll lA. 



DdSiN-K.i'si.s cAi'KiJATA (Suin'rhj/), 18:2(5. I'late XXVI 1 1, tigs. 7— JU. 

1826. Venu.s capkkata, J. de C Sowerhi/. Miii. CoiilIi., vol. vi, j). ol, [il. ilxviii, 

figs. IS. 
18.50. — ~ A. d'Orhlijitij. Prodr. de Pal , vol, ii, \,. 159. 

1854. Cytheuea — J. Morris. Cat. Brit. Poss., cd. 2, p. 200. 

18(j5. Venus capekata, F. J. Fidel and 0. Camjnche. Poss. Terr. Crct. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), 
p. 189. 
lst;8. — — .1. liridrl ami F. L. Cornet. Meule de Bracquegnies 

(Mem. cour. et Mem. des Sav. 
elrangers, vol. .\.\.\iv), p. 74, pi 
vii, figs. 6 — 8. 
1870. — — /•'. Shdli-Aa. Paheuiit. In.lica, Cret. Paumi S. ludia, 

vol. iii, p. 1(10 {Caryatis). 

V Noll |S|.-,. — — A. d'Orh'iijiiij. Pill. Fraiie Terr. Cret., vol. iii, p. 445, 

pi. eeel.\.\.\v, tigs. 9, 10 ( 1'. iiiiljijniiin. 
Prodr. de Pal., vol. ii, p. 236). 

Ih:sfrij)lii>)i. — Sliell oval, conve.x, uioderately or considerably iHe(|iiilateral ; 
length ratlier gieater than height. Antero-dorsal margin concave. Anterior 
margin rouiuU-d, pa.ssing gradually into the convex ventral margin. Posterior less 
convex tiian the anterior margin, sometimes subtrnncate. Postero-dorsal margin 
long, slightly convex. Unibones pidniinent, curved anteriorly. Ltuiule ovate. 
Pallial .■<inn.'^ lat her large, sulj-angidar. Ornamentation consists of strong, regular, 
concentric ribs. 

Hinge : Tn the right valve three stout cardinals separated dorsally, the anterior 
and median i)eing close together and nearly vertical, the posterior obliijue and 
divided hy a longitudinal groove ; there is an antei'ior elongate pit and a strong 
postei-ior lateral tooth. In the left valve the median is the stoutest of the three 
cardinals and is sometimes juincd dorsally to the neai'ly vertical anterior cardinal; 
the posterioi- cnnlinal is slender and \ery obliipie; the anterior lateral is strong, 
elongate and ])ar:illcl to the liiiiular ni;ti'gin. 

Mea.^arciiU'iif.s : 

(1) (^) i-i) W 

Leugth . ot . 31 . 30 . 128 . 

Height . :>0-5. 2'.» . 2G . 24.-5 . 

(1 H) Blaekdown. 
Ui'iimrks. — Internal castti from the Folkestone i3eds of I'ulborough were 
referred to this species by Forbes. I have not seen any s])ecimens which wcndd 
enable me to record the oeeurri'nee of l'. cupcrata in the Lower Creensand. 



{■>) 


(li) 


(') 


W 


2() 


. 2o , 


. 21 . 


15 mm 


22 


. 23 . 


18-5. 


14 „ 



CYPRIMKRIA. 183 

'I'lipc. — From Blackdown ; in the British Museiiin. 

Disfribittioii. — Upper (Treensixnd (zone of SrJilonihachia rosfrafd) of Bhickdown 
and Haldon. Recorded by Barrois from the Upper Greensand of Liilwortli, and 
by Jukes-Browne from the Upper Greensand of the Isle of Wight. 



Genus — ("yimmmeria, T. A. Conrad, 18G4. 

(•Proc. Acad. Nat. Sci. Philad.,' 18G4, p. 212, aud ' Amer. Journ. Couch.,' vol. ii, ]8CS, p. 102. 
Stoliczka, ' I'alieout. ludica, Cret. Fauna S. lu.lia,' 187li, p. 157.)' 

Suh-ffeniis — Cyclorisma, IF. //. Dall, 1903. 

('Proc. U.S. Nat. Mus.,' vol. x.xvi, 1903, p. 357. Syu. CyclothyrU, T. A. Conrad in W. C. Keir's 
'Geol. Rep. N. Carolina," vol. i, Appendi.K 1 (1875), p. 8. Non CyclotJiyris, M'Coy, 1844.) 



CYri(iMKi;i.\ (Cvclouisma) vectensis (Forhrs), 1845. Plate XXVIH, tigs. 11—18. 

1845. Venus vectensis, E. Forbes. Quart. Journ. Geol. See, vol. i, p. 240, pi. ii, 

fig. 4. 
18.50. — — A.iVOrhiiiny. Prodr. de Pal, vol. ii, p. 118. 

1854. — — ./. Morrh. Cat. Brit. Poss., ed. 2, p. 231. 

1805. — — F.J. Firtrl and a. Campiche. Foss. Terr. Cn't. Ste. 

Croix (Mater. Pal. Suisse, .ser. 4), 
p. 188. 
1870. — F. Stoliczka. Palteout. Indica, Cret. Fauna S. India, 

vol. iii, p. 160. 
? 1883. — — W. Keejjiiuj. Foss., etc. Neoc. Upwaro and Brickhill, 

p. 125. 

])p!<n-ipfi(in. — Shell oval, or nearly orbicular, a little longer than high, regularly 
convex, slightly or moderately inecjuilateral. Margin rounded. L'nibones small, 
pointed, somewhat curved forwards. Lunule indistinct, not impressed, limited by a 
Faint line. Pallia! sinus angiilar, directed upwards. Margins of valves smooth. 
Surface of shell smooth except for small, inconspicuous, concentric ridges, and 
occasional growth-rings. 

Hinge : In the riglit valve an anterior and a median cardinal and two posterior 
laminar teeth (which together represent the posterior cardinal) diverge from 
under the umbo; the anterior is directed forwards, the median is nearly vertical, 

' 'i'he following European species are referred by Conrad and In- Stoliczka to the j,'cniis 
Cyprimeria: C yclina primieva, Zitt., Dosivia cretacea, Zitt., Circe (liKriin (Math.), Circf cohciiiIiIch, 
Zitt., and AreoiHKjiii rotinidnf/i, d'Orb. Holzapfel figures Cypriiiirri'i (ieinHzi (Midi.) and C. motiela, 
Holz., from the Aachen Greensand. 



184 CRETArEOUS LAMELLIBRANCHIA. 

and the two posterior slope oblicpielv backwards. In the left valve a long, oblitpie 
laminar, posterior cardinal; a median cardinal (which is divided); and an 
anterior cai'dinal, diverge nnder th(> ninbo, from which they are separated by a 
narrow space or channel. In front of the anterior cardinal the anterior part of 
the hinge-plate is concave. 
Alcd.mrcments : 

(1) (2) (3) (4) (5) 

Length . 38 . 32 . 31 . 28 . 24 mm. 
Height . 34 . 20-5 . 20 . 2G . 22-5 „ 

(1—5) Crackers, Atherfield. 

Afjiidtirii. — This species shows some resemblance to Vcnvs rriidoppraiia 
(Leymerie), especially to the example figured by Pictet and Renevier,' but the 
umbones are less prominent and the lunide is less distinct. 

l^ypc. — The type came from the Crackers of Atherfield, ])nt cannot now he 
found. 

Distriliiifion. — Lower Greensand (Crackers) of Atherfield. Recorded from 
the Atherfield Clay and Bed vii of Atherfield by Fitton. Recoi-ded by Topley 
from the Atherfield Beds of Peasmarsh and Shalford.- 



Cvn;iMi.;i;]A (Cvclokism \) pakva {Sowrrh,/), 182(;. Plate XXVIII, figs. 19—23; 

Plate XXIX, figs. 1—3. 

1826. Venus parva, J. de C. Sowerhy. Miu. Concli., vol. vi, p. 32, ]il. dxviii, 

1845. LuciNA > soLiDULA, E. Forbes. Quart. Joiiru. Gi'ol. Soc, vol. >, ].. 239, pi. ii, 

fife'. 7. 
1850. Venus parva, A. d'Orhiijinj. Prodr. dePal., vol. ii, p. 159 (not Blackdown). 

— Llcina soi.idui.a, iVOrJiiijinj. Iliid., vol. ii, p. 118. 

1854. Cythkrea parva, ./. Murris. Cat. Bnt Foss., e^i. 2, p. 2(il ( purfim). 

— LuciNA 80I.IDULA, MoriiK Il)id., (d. 2, p. 208. 

1865. Venus parva, F. J. Pictet ami G. Campiche. Foss. Terr. Crcl, Ste. Croix 

(Mater. Pal. Suisse, ser. 4), p. 188. 
1870. — — F.StoUczka. PalfDont. ludiea, Cret. Fauna S. India, vol. iii, 

p. 16U {Ccrryalis). 

— LuciNA? solidula (PMysia), Stoliczka. Ibid., vol. iii, pp. 252, 262. 

? 1895. Venus rf. pakva, E. TieKseu. Zeitsebr. d. deutsch. geol. Gresellsch., vol. xlvii, 

p. 484. 



1 Pict«t and Kencvier. ' Foss. Terr. Aptieu' (' Mati'r. Pal. Suisse,' ser. 1, 1855-56), p. 71, pi. vii, 
% 9. Pictet :ind Canipiclie, 'Terr. Crct. Ste. Croix' ("Mat^r. Pal. Suisse,' ser. 4, 1865), p. l«l.pl.cxi, 
fi- 12. 

~ r liave not seen the specimen recorded l)\- Kei'pin>,' tiiim Upware. 



CYPRTMERIA. 185 

Non 1840. Venus pauva, A. GoJdfiiss. Pctref. Germ., vol. ii, p. 246, pi. cli, fif;. 4 

(V. Goldfufisi, Qe'nntY., 1850; V. gtihparva, 
d'Orbigny, 1850). 

— 1841. — — F. A. Itiimer. Die Verstein. d. nord-deutsch. Kreidefjeb., 

p. 72 (Venus snhinflexa, Kiiiner, 1836). 

— 1846. — — A. E. Reiii>s. Die Verstein. der bfihm. Kreideformat., pt. 2, 

p. 20, pi. .xli, figs. 16, 17. 

— 1863. — — A. V. Sfromheck. Zeitschr. <ler deutsch. gfol. GesclLsch., 

vol. XV, p. 146. 

— 1868. — — A. Briaii and F. L. Cornet. Meule de Bracquegnies (Mem. 

cour. et Me'in. des Sav. I'trangcrs, 
vol. xxxiv), p. 75, pi. viii, figs. 1, 2. 

— 1877. Cytherea PARVA, G. l?o/i»!. Zeitschr. der deutsch. geol.Gesellsch., vol. xxix, 

p. 241. 

— 1883. Vencs cf. PARVA, A. Fritsch. Stud, im Gobicte der biihm. Kruidefurniat., iii, 

Iserschicht., p. 109, fig. 77. 

— 1885. Venus parva, F. JViifliiui. Die Fauna d. baltisch. Cenoman. (PaliEont. 

Abhandi., vol. ii), p. 32, pi. v, fig. 11. 

— 18fl3, — — Fritsrii. Op. rit., V, Priesen. Sehicht., p. 98, fig. 118. 

Descriptidji. — Shell small, nval, convex, inoileratcly inequilateral. Antero- 
(lorsal margin slightly concave, or nearly straight, forming a rounded angle with 
the anterior margin which curves rapidly to join the convex ventral margin. 
Posterior margin rounded or .subtruncate. Postero-dorsal margin slightly convex. 
Umbones rather prominent, curved inwards and forwards. liunule broad, ovate, 
more or less projecting, limited l)y a groove. Pal Hal sinus large, angular. 
Ornamentation consists of small, somewhat irregular, coucenti'ic ribs, and occasional 
growth-rings. 

Hinge: In the rio-ht valve the antei'ior and median cardinals are stout and 
nearly parallel, and the two posterior teeth (wdiich represent the posterior cardinal) 
are oblique and diverging ; in front of the anterior cardinal is a groove, bounded 
by a ridge above and l)elow, parallel to the inner margin of the hinge-plate. In 
the left valve the antei-ior and median cardinal teeth diverge widely under the 
umbo and the posterior cardinal is oblique; the anterior cardinal is continued 
forward into a i-idge along the inner margin of the hinge-plate. 

Measurements : 

(1) (2) (3) (4) (5) 

Length . 20-5 . 21 . 20 . 20 . Ii) 
Height . 17 . 17-5. 17-5. 17 . 1<^> 

(1) P,-rno.-hca, East Sliair..rd, 
(2—8) Crackers, Atherfield. 
Affinities. — The differences between this species and ('. {Ct/dorimin) rofimiKjeiisin 
are given below. 

The foiin fiom IJiacquegnies, which was referred to Vitnix jitirrn by Hnart and 
Cornet, is less elongate. 



(«) 


r<) 


(«) 


1() 


. 1 !■ . 


10 nnn. 


1 1- . 


12 . 


s-o „ 



186 ('RP:TA(JE0US lamellirranchia. 

The hinge differs from tliat of other species of Ci/clonsmd in that the anterior 
tooth in tlie left valve is continued foi'wards into a ridge at the inner margrin of 
the hinge-plate. 

Liicina? fiolidiild, Forbes, appears to be identical with fV??7/.s parva, Sowerby; 
the type is missing, but other specimens which are in the Museum of tlie Geological 
Society and were probably identified by Forbes, are undoubtedly examples of 
V. j)arva. The typo of Lurinn? solidiila, so far as one can judge from the figure, 
seems to have been rather shorter than most examples of Venus pnrva. 

Venus Orbignyana, Forbes,' from the Crackers of Atherfield, is stated to be 
allied to T^. jxirra. The type is missing, but a specimen named T'. OrJiir/in/aiui in 
the Museum of the Geological Society a2:>pears to he a small example of ('i/prina 
Saussuri (p. 131). 

lismnrks. — Examples of this species vary somewhat in convexity, in relative 
heiglit and lengtli, in the proniiuence and position of the umbones, and in the 
projection of tlic hmule at the margin where the valves meet. The tj'pes are 
internal casts from I'arliain, and they agree, exce])t in being slightly more convex, 
with casts from Bast Shalford, whei'e specimens with the shell preserved are also 
found. The latter do not differ from the perfectly preserved specimens found in 
tlie Crackers of Atherfield. 

'I'l/ji''. — From the Sandgate Reds of I'liilunn Park, in the Rritish Museum. 

Pistrll'ii/idii. — fiower Greensand : /V;y/'^-bed, Crackers, and Red I--") of Ather- 
field. /'('/'//(^-lii'd of Sandown. Allicrlicld Reds of Reasniarsh and Slialf'oi'd. 
Sando-ate lieds of I'arliani Pai-k. 



Cvi'K'iMKi;: A (Cvcr.oi.MsiMA) K'oToiMACKNsis {(V Orhiijii ij) , 1S45. IMate XXIX, figs. 4 — 0. 

\8^h. Vknus iMioToMAiii-.Nsis, A. il'<_h-}iiijiiij. Pal. FiiUi<;. Terr. Cn't., vol. iii, p. 

443, ]>1. ccclxxxv, fitjs. 1 — 5. 

ISf)!!. ROTiioMAOKNSis, (VOrhiijinj. Prodr. do Pal., vol. ii, ]). 104. 

l.S(;.''). RoToMAf.KNSis, F. J. Pirlrl ,1)1(1 G. Coiiqjichc. Fo.ss, Ten-. Cn't. 

Ste. Croix (Mater. Pal. Suisse, 
ser. 4),p. 190. 

1870. - — F. Sf'ilirkza. Palreont. Indica, Cret. Faiiua- S. 

India, vol. iii, p. 161 (? Caryatis). 

RemarJ.-s. — The Knglish examples of this sjiecies are internal casts occasionally 
with small portions of the shell preserved. l)'()rl)igny's S})ecimens were obtained 

I -Quiirt. Joiiin. (leol. So.'.,' vol. i (1845), p. 240, pi. ii, Al,'. 5; d'Orbigny, 'Prodr. de Pal.,' 
vol. ii (1850), p. 118; Morris, 'Cat. Brit. Foss.,' ed. 2 (1854), p. 231 ; Piotet aud Campiche, ' Foss. 
T.'rr. Cn't. Ste. Croix' ('Mater. Pal. Suisse,' ser. 4. 1865) pp. 184, 188; Stoliczka, ' PalKont. Indica, 
Cr.'l. Fauna S. India,' vol. iii (]«7()), p. ICO. 



CVIMMMERIA. Iy7 

from tliL' tJeiioinaniaii of Rouen. English specimens agree with tliose founcl at 
Rouen, except that in many cases the shell is somewhat shorter relatively. The 
surface is ornamented with concentric ribs. In I'. {Ci/cLurisiua) rotoindt/t'n.slti thu 
shell is more convex, more inequilateral, and the postero-dorsal margin has a 
greater slope than in C. {('i/c/iirismd) jiiirru.. The hinge appeal's to l)e uid<no\vn. 

Distribution. — Base of the Chalk Marl of Maitlen Newton and Chard. Chlorilic 
Marl of Melhury, Woolcondte, Maiden Hi';idley anil the Isle of Wight.' 



CvriMMKKiA (Cvi'lokis.ma) faua {Soirrrlnj), 1.S27. IMate XXIX, Hgs. 7— 1:J. 

1827. Venus v\k\, J. dc C. Svwt;rhij. Miu. Cuiicli., vul. vi, p. 12!», [.Ldlxvii, fi;,'. 3. 

IS.'iO. — — A. iVOrh'ujiiij. I'nxlr. dePal., vol. i-i, J.. LW (^«(Wr»i)- 

1854. — —J. Morris. Cat. Brit. Foss., ed. 2, p. 230 (pariivi). 

1868. — — A. Brlart and F. L. Curncf. Meule de Bracquej^uius (Mi'ui. 

cour. et Mi''iii. des Sav. I't rauj,'ers, 
vol. xxxiv), J). 73, j)l. viii, tif^s. 

y, 10. 
1870. — — F. Stoliczlca. Pul;ioiit. indica, Cret. Fauna S. India, vol. iii, 

1>. i(;o. 
1873. — — II. I). Ociiiitz. Das lilbthalgol>. iu Sachseu (Pala-'outo- 

graphica, vol. xx, pt. 2), p. 65, pi. xviii, 
figs. 9, 10. 
? 1882. — J. Kiesou). Sclirift. d. uat. (Icsellsch. iu Danzig, N.F., vol. v, 

p. 239. 
!' 1885. — — F. Niilliitij. Die Fauna <1. haltisL-li. Cononian. (I'alx'out. 

Al)liandl., Vol. ii), p. 32, pi. vi, tig. 1. 

Non l.SK). — A. Goldfms. Petrcf. Germ., vol. ii, \<. 217, pi. rli, tig. ('> (P. 

xithfidia, d'Orhigny ). 

— 1843. — — H. D. Gcinitz. Die Versteiu. von Kiesliugswalda, p. 13, pi. ii, 

figs. 7—9. 
'i — 1845. — ~ A.d'Orhhjinj. Pal. Pranv. Terr. Cret., vol. iii, p t-t-t, pi. 

ccclxx.w, figs. G — 8. 
1846 — — A. E. Eeusa. Die Verstein. der bohni. Kreideforniat , |.t. 2, 

p. 21, pi. xli, tig. 12. 

— 1847. — — J. Midler. Petref. der Aaehen. Kreidef., pt. 1. p. 24. 

— 1859. — iMMEKSA, Midler. Ibid., Supplement, p. 13. 

— 1863. ^ FABA, A. V. Stromheck. Zeitschr. d. deulsch. geol. Gesellseli., vol. 

XV, p. 147. 



1 Au ira^xji-fect left valve from the Cenomanian (Bed 12) of Wbitecliff, South Devon, was 
identified by C. J. A. Meyer with Veiiiig Goldfiisxi. Geinitz, ' Das Quadersaudst. oder Kreidegeb. iu 
Deutschland ' (185U), p. 154, pi. x. figs. 7, 8 ; ' Das Elbthalgeb. iu Saehseu ' (' Palueoutogi-aphicu,' vol. 
XX, pt. 2, 1873), p. 67, pi. xviii, figs. 16, 17. There is not sulficieut evidence to confirm this ideutificu- 
tion ; the anterior part of tlie specimen is more produced than in the case of the examples figured by 
Geinitz. 



188 CRETACEOUS J.AMEEI.lJUtANCll I A. 

Nou 1803. Venus kaba, H. Dreschtr. Ibid., vol. xv, p. 3-13. 

— 1884. CrrKiMEKiA faba, E. HohaiiJ'd. Ibid., vol. xxxvi, p. 4t)7, pi. vii, fig. 1. 

— 1889. Tapes faba, E. B.ohai>fel. Die MoUusk. Aaclieu. Kreide (Palseonlo- 

i,'r;ipliicii, vol. xxxv), p. 1G5, pi. xiii, figs. 7-lU. 

— 1897. Venus (Tapesj faba, A. Fritsch. Stud, iiii Gubiete dor boLm. Kreide- 

forinat., vi, Clilomek. Schiclit , p. G3, 
fig. 80. 

— 1901. — — — F. StufiH. Jalirb. d. k. preussisch. geol. Laudesuust. 

fiir 1900, vol. xxi, p. 82. 

Descriptum . — Shell oval, of moderate ctjiivexity, witli flattened sides, con- 
sidei'ably iiK'{|uilateral. Antero-dursal margin short, slightly concave. Anterior 
margin rminded, passing gradually into tlic sliglitly convex ventral margin. 
Postero-dorsal margin long, slight!}' convex, with a moderate or cousidei'able 
ventral slope. Porterior margin short, rounded or suhtruncate. Umbones small. 
Lunule elongate, not impressed, faintly limited. Ormimentation consists of small, 
regular, concentric ribs. 

Hinge: In the right valve the anterior and median cartlinals are stout, diverge 
slightly, and are directed forwards, and reach the lower margin of the hinge- 
plate; the two posterior teeth (wliicli represent the posterior cardinal) are 
laminar, oblique and diverging. In the left valve the anterior and median 
cardinals are rather stout and divei'ge; the posterior cardinal is slender and 
obliijue. In front of the antei'ior cardinal there is a concave space on the hinge- 
plate in hoth valves. 



Measureme), 


Us : 






















(1) 


(2) 






(3) 




(4) 


(5J 


Length 




30 


29 




. 


29 




28 


27 mm. 


Height 




25 


24 






22 


. 


21 


22 „ 








(1- 


-5) 


Blackdown. 








AJJi'iiUies. — 


-Veil UN An 


■lihli-idiui, 1 


d'Orbi 


igny,' f 


rom 


the Seuiinian 


of Charente 



Inferieure, is somewhat simihii' in form to ('. {Cijrlorisina) j'nlxi, but the surface 
oF the shell is smooth. 

A species found in tlie Aachen Greensand has been identified by Goldfuss, 
Holzapfel, and others with Sowerby's I'eiuis faha, but was regarded as distinct by 
(r()rl)igny ami G. Miillei'. It differs from Sowerby's species in the greater 
cui'vature of the ventral margin and the moiv pointed posterior extremity ; also the 
posterior teeth in the right valve are less widely separated and are more oblique. 

In d'Orbigny's figure of Venus faba the ornamentation is coarser than in English 
examples, but a s[)ecimen from the Cenomanian of Rouen (one of the localities 
cited by d'Orbigny) differs but little in this respect from Blackdown specimens. 

Remarks. — The principal variation consists in the amount of the ventral slope 
1 i'al. I'lauv- Terr. Crtt.,' vol. iii (1845), p. 449, pi. ccclxxxvi, figs. t>, 7. 



CLEMENTIA. 189 

of the postez'O-dorsal margin. In the type specimen that slope is small, so that 
the outline of the shell is distinctly oval. The position of the umbones also varies, 
so that some specimens are more inefjuilateral than others. 

Specimens found in the Gault of Black Ven ai'e usually somewhat crushed and 
often larger than Blackdown examples ; some are more elongate and agree closely 
with Vemifs sublasvis, Sowerby (see below). 

Ti/jje. — From Blackdown ; in the British Museum. 

Distrihntion. — Upi)er Greensand (zone of ScJihMuhuchia rontratti) of Blackdown 
and (?) Devizes. Gault of Black Ven. 

Cyprimeria (Cyclouisma) subl^vis (Soioerhi/), 183G. Plate XXIX, fig. 14. 

18.36. Venus? subl^vis, J. de C. Sowerby. Traus. Geol. Soc, ser. 2, vol. iv, pp. 

242, 342, pi. xvii, fig. 5. 
1850. Venus subl.bvis, A. d'Orhiyny. Prodr. de Pal., vol. ii, p. 159. 
1854. — — /. Morris. Cat. Brit. Foss., ed. 2, p. 2.31. 

1870. — — F. Sloliczka. Palseont. Indica, Cret. Faima S. India, 

vol. iii, p. 161. 

BemarJcs. — The only specimen which I have seen is the type. It differs from 
G. {Gydovisma) faba only in being more elongate, and seems to be merely an 
individual variation. Venus immersa, Sowerby,^ also known by the type only 
(Plate XXIX, fig. 15), does not appear to differ from V. suhlaimfi. The types of 
both are in the Bristol Museum and come from the Upper Greensand of Blackdown. 

4 

Genus — Clementia, ./. E. Gray, 18-40. 
(' Synopsis Brit. Mus.,' p. 149.) 

Sub-genus — Flaventi.x, A. J. Jnkes-Browne, 1908. 
(' Proc. Malacol. Soc.,' vol. viii, p. 167.) 

Clementia (Flaventia) Ricokde^vna (d'Orbu/ny), 1845. Plate XXIX, figs. 16 — 18. 

1845. Venus Eicobdeana, A. d'Orbigvy. Pal. Franv. Terr. Crot., vol. iii, p. 431, 

pi. ccclxxxii, figs. 1, 2. 



1 Sowerby, 'Trans. Geol. Soc.,' ser. 2, vol. iv (1836), pp. 242, 342, pi. xvii. fig. 6; d'Orbigny, 
'Prodr. de Pal,' vol. ii (1850), p. 159; Morris, 'Cat. Brit. Foss.,' ed. 2 (1854), p. 231 ; Stoliczka, 
' Palajont. Indica, Cret. Fauna S. India,' vol. iii (1870), p. 161. Nou Venus immersa, Midler, ' Petref . 
der Aacbeu. Kreidef.,' Suj.pleuient (1859), p. 13; Eeuss, ' Die Verstein. der bohm. Kreideforniat.,' 
pt. 2 (1846), p. 20, pi. xli, fig. 11 ; Kner, 'Denlischr. d. k. Akad. Wissenscb. Wieu, Matli.-Nut. CI.,' 
vol. iii (1852), p. 311. \<l. xvi. tig. 20. 

25 



I'.H) CRETACEOUS LAMELLIBRANCIIIA. 

1850. Venus Kicoedeana, A. d'Orbiyiii/. Prodr. dt- Pal., vol. ii, jj. 7(j. 
1855. — — G. Cotteau. Moll. Foss. de I'Youne, p. (34. 

1865. — — F. J. Pldet uiul G. Campiche. Foss. TeiT. Civt. Ste. 

Croix (Matt'r. Pal. Suisse, ser. 4), 
p. 169. 
1870. — — F. Sloliczka. Palaiout. ludiai, Cret. Fauna S. India, 

vol. iii, p. 159. 



Deacrijjtioii.— Shell ovul, convex with flattened sides, considerably inequilateral, 
anterior part higher than the posterior part. Anterior margin regularly rounded, 
passing gradually into the slightly curved ventral margin. Postero-doi-sal margin 
long, convex, with a considerable ventral slope. Posterior margin short, oblique, 
forming a rounded angle with the ventral margin. LFmbones broad, curved 
forwards. The part of the shell behind a line between the umbones and the 
postero-veutral angle slopes rapidly from the flattened sides. Luuule elongate, 
limited by a groove. Escutcheon elongate, deep, limited by a sharp edge. 

Ornamentation consists of sharp concentric ridges. Pallial sinus angular, 
somewhat ascending. 



Measurements .- 












(1) 


(2) (3) 


(4) 


(5) 


Length 


56 


52 . 52 . 


5U 


43 mm 


Height 


47 


40 . 39 

(1) Atberfield Beds, Peasmarsli. 
(2, 5) Po-Ha-bed, Atberfield. 

(3) Hytlie Beds, Lympue. 

(4) Hytlie Beds, Pulborough. 


35 


34 „ 



4//i'/'i^"'''*-— English specimens difl:'er from d'Orbigny's figure in the more ra[iid 
ventral slope of the postero-dorsal margin. I am indebted to Professor Boule for 
comparing photographs of specimens from the Lower Greensand with the examples 
in the d'Orbigny collection which appear to l)e the types, and he states that in 
the latter the shell is less elongate and the postero-dorsal l)order has a greater 
slope than in d'Orbigny's figure, consequently the photographs agree much more 
closely with the types than with the figure. M. A. de Grossouvre has been good 
enough to lend me a specimen of G. (Plaventin) Riconlciinit from the Lower Aptian 
of Seignelay, Yonne, one of the localities mentioned l)y d'Orbigny, and a 
comparison of that with English exam})les leaves no doubt as to their specific 
identity. 

The generic position of Clement ia {Vlarentvt) Rico rdea tut is at present some- 
what uncertain since none of the specimens shows the hinge ; but on account of 
the resemblance in the form of the shell to that of (!. {Flaventia) omiis it is 
probable that this species belongs to the sub-genus Flaventia. C. (Flaventia) 



CLEMENT! A. 191 

Ricordeana is less elongato and its postero-dorsal margin is iiinre convex and slopes 
more rapidly than in Venns suh-Brnngninrtiann, d'Orbigny.' 

Remnrlcit. — This is probably the species which has been recorded by some 
authors from the Lower Grreensnnd as Vevm^ nvalis and Asfarfr s^vJistrinta, Leymerie. 
The proportions of length and height vnry considerably in different specimens. 

Distribution. — Lower Greensand (/^'9-»rt-bed) of Atherfield. Atherfield Beds 
of East Shalford, Redhill, and Pensinarsh. Hythe Beds of Hythe, Lympne, and 
I^nlbornnofli. 



Clementia (Flaventia) ovams {Sowerhy), 1827. Plate XXIX, figs. 19— 2*). 

1827. Ventjs ovams, .7. de C. Sowcrhy. Min. Conch., vol. vi. p. 129, [il. dlxvii, 

fig. 1 (not fig. 2). 
18.50. — —A. (VOrhigny. Prodr. de Pal., vol. ii, p. 159. 

18.54. — — J. Morris. Cat. Brit. Foss., ed. 2, p. 2S1 (not from the 

localities given). 
1870. — — F. Stolrczha. PaliEont. Indica, Cret. Fauna S. India, vol. 

iii, p. 160. 

Nonl840. - —A. Goldfiiss. Petref. Germ., vol. ii, p 247, pi. eli, fig. 5 

{Venus subovalig, d'Orbignj, 18.50). 

— 1846. — — A. E. Reuss. Die Verstein. der biJhm. Kreideformat., pt. 2, 

p. 21, pi. xxxiv, fig. 22. 

— 1847. — — /. Mailer. Petref. der Aachen. Kreidef., pt. 1, p. 24. 

— 1870. — — n. Credner. Zeitschr. d. deiitsch. geol. Gesellsch., vol. xx, 

p. 191. 

— 1884. Cytherea ovalis, E. Holzapfel. Ibid., vol. sxxvi, p. 464, pi. vii, figs. 2 — 4. 

— 1888. — — G. Mailer. Jahrb. d. Ic. preussisch. geol. Landesanst. fiir 

1887, p. 427. 

— 1889. — — E. Holzapfel. Die Mollusk. Aachen. Kreide (Palseon- 
^ tographica, vol. xxxv), p. 169, pi. xiii, 

figs. 11—15. 

— — Venu.s — A. Fritgch. Stud, im Gebietc der biihni. Kreideformat., 

iv, Teplitz. Schicht., p. 80, fig. 69. 

— 1898. Cythehea — G. Mailer. Mollusk. d. Untersen. v. Braunschweig u. 

Ilsede, p. 66. pi. ix, fig. 15. 

— 1901. -- — F.Sturm. Jahrb. d. k. preussisch. geol. Landesanst. fiir 

1900. vol. xxi. p. 83. 

Z)(?.5ci-i2)<ioH.— Shell elongate-oval, of moderate convexity, considerably inequi- 
lateral. Antero-dorsal margin rather long, concave. Anterior margin rounded, 

' Leymerie, 'Mem. Soc. geol. de France,' ser. 2, vol. v (1842), pp. 5, 25, pi. v, fig. 7; d'Orbigny, 
' Pal. Fran?. Terr. Crc't.,' vol. iii (1845), p. 4:52, pi. ci.lxxxii. figs. 3—6; Pictet and Campiche, 'Terr. 
Crt't. Ste. Croix' (1865), p. 168. pi. cxi, fig. 1. 



192 CRETACEOUS LAMET.LTBRANCHIA. 

passing gradually into the coTisideral)ly curved ventral margin. I'ostero-dorsal 
margin long, convex. Posterior margin sliort, rounded. Umbones prominent, 
pointed, with a considerable anterior curvature. Lunula ovate, faintly limited. 

Ornamentation consists of growth-rings and (in well-preserved specimens) of 
numerous small, regular, concentric ribs. Pallial sinus deep, ascending, with 
rounded end. 

Hinge : In the right valve the anterior and median cardinals are strong, and 
diverge below the iimbo ; the posterior cardinal is long, oblique, curved, and 
divided into two parts of which the anterior is shorter than the posterior. In 
the left valve the anterior and median cardinals are strong and diverge below 
the umbo ; the posterior cardinal is laminar and very oblique. 

Measurements : 

(1) (2) (:i) (4) (5) (6) 

Length . 44 . 40 . 37 . 34 . 32 . 30 mm. 
Height . 33 . 31 . 32 . 2G . 27 . 23 „ 

(1 — 6) Blackdown. 

Affinitux. — The form from the Aachen Greensand which was referred to this 
species by Groldfuss and others possesses an anterior lateral tooth. 

Remarks. — In Sowerby's figure the lunule projects more than in any specimen 
which I have seen, l)ut in other respects the examples from Blackdown agree with 
that figure. 

Type. — The type came from Blackdown, but cannot now be found. 

DistriliuUon. — Upper Greensand (zone of Schlnmbachiarosfrafa) oi Blackdown.' 
Recorded by Jukes-Browne from the Upper Greensand of Devizes. 



Genus — Cai.lista, O.A.L. Morcli, 1853. 
('Catalog. Conehvl. de Yoldi,' ii, p. 27.) 

Callista plana (Sowerhi/), 1813. Plate XXX, figs. 1—6. 

1813. Venus planus, .7. Soircrhij. Miu. Couch., vol. i, p. 58, pi. xx, lower figures. 
1854 Cytherea plana, J. Morris. Cat. Brit. Foss., ed. 2, p. 201. 
? 1845. Venus plana, A. d'Orhiyny. Pal. Frauf. Terr. Crt't., vol. iii, p. 4-t7, pi. 

ccclxxxvi, figs. 1 — 3 (? partim). 



1 The type of Venus siihmersa, Sowcrby, from the Upper Grroensand of Pinhay, cannot be found. 
I have seen no specimen which could be referred to that species. Barrois, however, records it from 
the Upper Greensand of Liilwcirth. .T. de C. Sowerby, 'Trans. Geol. Soe.,' ser. 2, vol. iv (1836), pp. 242, 
342, pi. xvii, fig. 4 ; d'Orbigny, ' Prodr. de Pal.,' vol. ii (1850), p. 159 ; Morris, ' Cat. Brit. Foss.,' ed. 2 
(1854), p. 231 ; Stoliczka, ' PaUeout. ludica, Cret. Fauna S. India," vol. iii (1870), p. Kil (Caryatiii) 
Barrois, ' Terr. Cret. Super, de TAuglet. et do I'lrelande ' (187(!), p. 90. 



CALLISTA. 193 

1850. Venus plana, A. d'Orhignij. Prodr. de Pal., vol. ii, p. 159. 
1866. — — F. J. Pictef and G. Cawjnche. Foss. Terr. Cn't. Ste. Croix 

(Matur. Pal. Suisse, ser. 
4), p. 190. 
18G7. — — E. Gueraiujcr. Album Pak'ont. de la Sartho, p. IS, pi. xvii, 

fig. 11. 
1868. — — A. Briiirt aniJ F. L. Cornet. Meuli'de Bracquegnies (Mem. 

cour. et Mem. des Sav. 
(■trangers, vol. xxxiv), p. 72, 
pi. viii, figs. 3 — 5. 

? Nou 1846. Venus plana, A. E. Revss. Die Ver.stein. der bdhm. Kreideformat., pt. 2, 

p. 21, pi. xli, fig. 14. 

? — 1879. Cytheeea (Cabtatis) plana, /. F. Whiteaves. Mesoz. Foss., vol. i (Geol. 

Surv. Canada), p. 149, 
pi. xvii, fig. 14. 

Description. — Shell oval, sometimes more or less triangular, rounded, moderately 
convex, considerably inequilateral ; length greater than height. Antero-dorsal 
margin long, concave. Anterior part of valve more or less produced, with 
rounded margin. Ventral margin forming a considerable curve. Posterior margin 
short, rounded or slightly truncate. Postero-dorsal margin convex, much longer 
than the antero-dorsal margin. Umbones rather prominent, pointed, close 
together, curved anteriorly. Lunula long, cordiform, distinctly limited. 
Escutcheon not defined. Ornamentation consists of small concentric ridges, with 
stronger growth-ridges at intervals. Fine radial ril)bing is occasionally seen in 
tlie posterior part of well-preserved specimens. Pallial sinus fairly large, angular 
or sub-angular, slightly ascending. 

Hinge : In the right valve the anterior and median cardinals are nearly 
vertical, slightl}' diverging, and separated dorsall}^ the posterior cardinal is 
oblique, long and divided, its posterior part is much longer than the anterior part, 
and the latter nearly meets the anterior cardinal under the unil^o ; in front of the 
cardinal teeth there is a shallow, elongate pit with slightly raised upper and lower 
margins. In tlie li>ft valve the stout anterior and median cardinals diverge from 
mider tlie uinl)o, tlie anterior tooth l)eing nearly vertical; there is a long slender, 
obli(|ue posterior cardinal, and an elongate, ridge-like anterior lateral tooth, wliich 
is grooved or corrugated. 

Measiirr})ii')ifs .- 

(I) (2) (H) (4) (-.) (C) (7) (8) (9) 

Lengtli . 72 (i'.» CO Crl M r,2 1-8 4I. 35 mm. 
Hciglit . r,3 .-,7 53 51 4.() 43 M 37 29 „ 

(1—9) Blackd.nvii. 

Al}i)iitirs. — Specimens from Senonian deposits of Kurope have been referred to 



194 CRETACEOUS LAMELTJRRANCHTA. 

Venus flamiii, Sowerby, by several authors; ' and so far a.s I can jiulgo from the 
few figures which liave been puljlislied, tliey seem to differ but little from 
Sowerby's species. The example from Aachen figured by Goldfuss agrees closely 
with specimens from Blackdown except that the bniiilc projects more at the 
margin. Holzaj^fel has compared Aachen with Blackdown specimens, and 
confirms Goldfnss's identification. The example figured liy d'Oibigny" differs 
in having a large and deep escutcheon. 

Specimens from the Ti-ichinopoli Group (near the base of the Ariyalur Gi'oup) 
were identified by Stoliczka'^ with Vmvs flavva. 

The absence of a channel under the anterior right cardinal, and lh(> occurrence 
of fine i-adial ornamentation connect this species with Gallista. The pallial sinus, 
however, resembles that of Pifuria. The anterior lateral tooth in the left valve is 
much less prominent, and the corresponding pit in the right valve much smaller 
and shallower than in either CaUisfa or Pitaria. This species is the type of the 
section or sub-genus CaUutwa, Jukes-Browne.* 

Remarks. — This is a common fossil at Blackdown. The variations seen 
consist in the proportion of height to length, the more or less triangular or oval 
outline, and the more or less produced anterior part of the shell. 

Tyj)e. — From Blackdown ; in the British Museum. 

Bit^frUndinn. — Upper Greensand (zone of SchloonhacJiin rostrafn) of Blackdown 
and Haldon. Recorded by Jukes-Browne from the Upptn- Greensand of Devizes, 
the Isle of AViffht, etc. 



o 



Family— CATIDUDJE, Lamard-. 

Genus — Protocardia, E. Beyrirh, 1845. 
(' Menke's Zeitschr. f. Malakozool.,' p. 17.) 

PijoTOCATMMA ANfiMOA, sp. nov. Plate XXX, figs. 7 n,h; Plate XXXT, fig. 1. 

Descripfiini. — Shell large, convex, with flattened sides, sulxpiadrate, luoderately 

1 Goldfuss, ' Petref. Germ.,' vol. ii (1840), p. 2:i8, pi. cxlviii, fig. 4 ; Miiller, ' Petref. der Aiuheii. 
Kreidef.,' (1847), pt. 1, p. 25; Dresclier, 'Zeitschr. d. deutsch. geol. Gesellsch.,' vol. xv (186-3). p. 
344; Brauns, ' Zoitsclir. f. d. tjesammt. Naturwiss.,' vol. xlvi (1876), p. 308; II. SchWidor. 'Zeitschr. 
d. deutsch. geol. Gcsdlsch.,' vol. xxiv (1882), p. 27.T ; Holzapfel, 'Die MoUusk. Aachen. Kreide' 
(' Palseoutograpbica,' vol. xxxv, 1889), p. 171, ]il. xiii, figs. 16 — 18; Vogel, ' Holland isch. Kreide' 
(1895), p. 42. 

2 D'Orbiguy subsequontlv separated the Senouiau form under I lie name Venn)) suhpIaiKi. ' I'ludr. 
de Pal.,' vol. ii (1860), p. 237. See also V. Renavxiava, d'Orbigny, ibid., p. 194. 

•■* Stoliczka, 'Palseont. Indica, Cret. Fauna S. Indi;!,' v<.l iii (1870), ]>p. 151, ICO, li;9, pi. vii. figs. 
1—4. 

^ Proc. Malacol. Soc, vol. viii (1908), p. 156. 



PROTOCARDIA. 195 

inequilateral, luugtli and height nearly equal. Antero-dorsal margin nearly 

straight. Anterior margin convex, curving rapidly to join the ventral margin, 

which is moderately or slightly convex. Posterior margin truncated, forming 

angles with the ventral and postero-dorsal margins. Umbones large, curved 

forwards, with a sharp carina extending in a curve to the postero-ventral angle 

and limiting the flattened, steeply-sloping posterior area, the dorsal portion of 

which is concave. Shell depressed in front of the umbones. 

Ornamentation : Sides of shell nearly smooth except for numerous, \evy small, 

concentric ribs which are separated by fiat interspaces. The posterior area is 

covered, except near the postero-dorsal margin, by 12 strong radial ribs. 

MeiiHuremeuts : 

(1) (^) (3) 

Length . 80 . 7G . 46 mm. 

Height . 78 . 71) . 40 „ 

(1 — 3) Crackers, Atherfield. 

Acuities. — This species resembles J'. Forhesi (Pictet and Renevier),^ from the 
Lower Aptian of Ste. Croix, but the umbones are less prominent, and the ribs on 
the posterior area are less numerous. 

It is also similar to P. iiu.jjre^sa (Deshayes),~ but is distinguished by the 
smaller curvature of the ventral margin, the greater flattening of the sides of the 
shell, and the more considerable curvature of the umbones. 

Distribatioii. — Lower Greensand (Crackers) of Atherfield.* 



PiiOTorAuniA spn.KROiOEA {Forbes), 1815. Plate XXXI, tigs. 2, S. 

1845. Caedium sPHasRoiDiUM, E. Forbes. Quart. Jouru. Guol. Soc, vol. i, 

\i. 243. pi. ii, fig. 8. 
1850. — — A. iVOrhujiiij. Prodr. de Pal., vol. ii, p. 79. 

1852. — NECKEKiANUM, F. J. Fictiit uiid \V. Roiix. MoU. Foss. Ores 

verts de Geneve, pp. 424, 
425, pi. XXX, fig. 3. 
— — si'UJiuoiDKUM, Fidft and Roax. Ibid., p. 546. 

1854. — —J. Morris. Cat. Brit. Foss., ed. 2, p. 193. 

1 'Foss. Terr. Aptien ' ('Mater. Pal. Suisse,' ser 1, 1856), p. 79, pi. viii, fig. 4; Pictet aud 
Caiiipiuhc, 'Terr. Crct. Ste. Croix (Matur. Pal. Suisse, ser. 4, 18(50), p. 261. 

^ D'Orliiguy, -Pal. Fraut. Terr. Cret.,' vol. iii (1841.), p, 20. pi. ccxl ; Pictet aud Caiupiche, 
op. cit., p. 249. 

* Some specimeus of Protocardia t'rojn the Lower Greeusand of Atherfield were referred by Forbes 
to Cardium peregrinorsum, d'Orbiguy, but that ideutificatiou was doubted by Pictet and Campiche. 
The speciuicus at present available arc iusufficieut for exact deteruiinatiou. See Forbes, * Quart. 
Jouru. Geol. Soc.,' vol. i (1845), p. 243. 



(.1) 


(5) 


G9 


47 mm. 


87 


48 „ 



ion CRETACEOUS I.AI^IKTJJI'.RAXdlTA. 

185{). Caudium spiia;koideum, F. J. I'irtd and E. Renevier. Foss. Terr. Aplicu 

(Mati'r. Pal. Suisse, ser. 1), 
p. 77, pi. ix, fig. 3. 
1866. — — F. J. I'ictet and G. Cumpiche. Foss. Terr. Cn't. 

Ste. Croi.x (Mati'r. Pal. Suisse, 
ser. 4), p. 260. 
1871. — — {y JjM\icaruivm), F.Stuliczka. Palseont. Indica, 

Cret. Fauna S. India, 
vol. iii, ]i. '213. 

Dt'^crvption. — Shell stdut, lai'L;t', iiiucli iiitlatcd, liio-lioi- tlian long, slightly 
inequilateral. Anterior and ventral niai'gins rounded. i'o.sterior niai'gins trun- 
cated, forming angles with the postero-dorsal and ventral margins. Umbones 
prominent, with a small forward curvature, and an inconspicuous carina extending 
to the postero-ventral angle and limiting the flattened postero-dorsal area. 

Ornamentation consists of regular, broad, flat, concentric ribs separated by 
narrow grooves. On the posterior area strong growth-ridges are present. 
Measurement a : 

(1) (^) (3) 

Length . 79 . 76 . 73 . 
Height . 84 . 91 . 87 . 

(1—5) Pcrna-hiiCi, Isle of Wight. 

Affinities. — Pictet and Campiche state that this species is very near to 
C. imhricatarium (Deshayes),^ but that the posterior area is more flattened and 
forms an angle with the sides of the shell ; also the truncated posterior margin is 
relatively longer. 

Remarks. — In this species the radial ornamentation of the posterior area is 
either very indistinct or quite obsolete. There is considerable variation in I'elative 
height and length of the shell. 

Type. — From the Lower Greensaud {rcriui-hed) of Saudown ; in the Museum 
of the Geological Society. 

Distribution. — Lower Greensand {Fcnia-htid) of Atherfield and Saudown. 
Recorded by Topley from the Hythe Beds of Hythe. 

Pbotocaedia, sp. Plate XXXI, flg. 4. 

The collection of Upper Greensand fossils made by the late W. Vicary, which 
is now in the British Museum, contains two imperfect right valves (No. L 17041) 

1 D'Orbigny, ' Pal. Franc;. Terr. Crct.' (1844), vol. iii, p. 18, pi. ccxxxix, figs. 4 — 6; Leymerie, 
'Mem. Soc. geol. de France,' ser. 2, vol. v (1842), p. 4, pi. v, tig. 2; Pictet and Campiche, 'Terr. 
Cret. Ste. Croix' ('Mater. Pal. Suisse,' ser. 4, 1866), p. 258, pi. cxxi, figs. 6, 7. The specimens referred 
to C. imhricatarium by Forbes are examples of Unicardium vectense (p. 163) ; see Forbes, ' Quart. 
Journ. Ueol. Soc.,' vol. i (1846), p. 243. 



PROTOCARDIA. 197 

from Haldon, wliicli resemble in sliape the higher forms of P. ffpliseroidea, but the 
umbones are narrower and more curved, and tlie carina is more distinct. 
Better specimens are needed before a satisfactory comparison can be made. The 
occurrence of F. sphseroidea in the Upper G-reensand (zone of Pecten asper) of 
Wihshire has been recorded by Mr. Jukes-Browne. 



Protogaudia, sp. Ph^te XXXI, fig. 5 a, b. 

Description. — Shell globose, witli rounded outline, slightly inequilateral, height 
and length nearly eipial. Umbones low, curved anteriorly. The posterior 
part of the shell (except near the postero-dorsal margin) is ornamented with from 
ten to twelve strong radinl ribs; the remainder of the shell bears numerous, small 
concentric ribs. 

Ajfinitie.i. — This species resembles P. peregrinorsa (d'Orbigny),^ but the area 
with radial ribs is relatively larger, and the concentric ribs are finer. 

Remarkx. — The only specimens seen are two iu the Museum of Practical 
Geology and two in Mr. Lamplugh's collection. 

Dititriliiiiinn. — Speeton Clay (zone of Pelemnites latendi.i, D, 4) of Speeton.- 



PuoTOCAiiDiA Hii.LANA {Soioerbij), 1813. Plate XXXI, figs. G a—c ; Plate XXXII, 

fig. 1—0. 

1813. Cakdium Hillanum, J. Sowerly. Miu. Couch., vol. i, p. 41, pi. xiv 

(upper figure). 
1819. — — Lamarrk. Hist. u;it. Auiiii. sans Vert., vol. vi, p. 20. 

1837. — —A. Goldfuss. Petret. Germ., vol. ii, p. 220, pi. exliv, 

fig. 4. 
— — — F. Dujardin. Mum. Soc. gcol. de France, vol ii 

p. 224. 

1840. — — H. B. Geliiitz. Char. d. Schicht. u. Petrcf. des 

siichs. Kreidegeb., pt. 2, p. 53. 

1841. — - F. A. Riimer. Die Verstein. d. nord-deutsch. 

Kreidegel)., p. 71. 

1842. — ]\KtiUKNiAisui\], r. Matlnron. Catal. Foss. du Depart, des 

Bouches-du-Rhone, p. 157, 
pi. xviii, fig. 6. 



' 'Pal. Fran^. Terr. Cret.,' vol. iii (1844), p. 1(!, pi. cixxxix, figs. 1 — 3; Pictet and Campiche, 
• Terr. Cret. Ste. Croix ' (' Mater. Pal. Suisse,' ser. 4, 1866), p. 254, pi. cxxi, figs. 1, 2. 

- Internal easts of a globose and nearly e(|uilater:il " Canlium" (perhaps ProtocanUn), from the 
Spilsby Sandstone ot Douniugton, are in the Sedgwick Museum. 

2G 



1«J8 CliETA{!EUUS LAMELIJHRANCHIA. 

1843. Cardium Hillanusi, II. B. Geiuitz. Die Verstcin. voii Kieslingswalda, 

p. 13, pi. ii, tigs. 10, 11. 

1844. — —A. d'Orhhjnij. Pal. Frauy. Terr. CnH , vul. iii, p. 

27, pi. cfxliii. 

1845. Pkotocardia Hii.i^A.tiA, E. Bayrich. Meuke'sZeitsclir. f. Malakozool., p. 18. 

1846. — — A. E. Kftisn. Die Versteiu. dor buhui. Kreide- 

format., pt. 2, p. 22, pi. xlv, 
fig. 2. 

— — — II. Ii. Griiiitz. Griiudr. d. Versteiu., p. 421, 

pi. xix, fig. 4. 
y — Cardium Hillanum, E. Forhcs. Traus. Geol. Soc, scr. 2, \o\. vii, p. 146. 
1850. — —A. d'Orhiijny. Prodr. de Pal, vol. ii. ].. 162. 

Protocardia Hillana, H.B. Geinitz. Das Quadersaudst. odevKreidegeb. 

iu Deutschlaud, p. 1.54. 
? 1852. Cardium Hillanum, F. Riimer. Kreidebild. v. Texas, js. 49, pi. vi, fig. 12. 

— Protocardia Hillana, H. G. Bronn. Letliaea Geogn., vol. ii, p. 302, 

pi. XXX, fig. 12. 
1854. Cardium bifrons, A. E. Eeiiss. Kreideschicbt. i. d. Ostalpen, p. 145, 

pi. xxviii, fig. 19. 

— — Hillanum, J. Morrii'. Cat. Brit. Foss., ed. 2, p. 192. 

1863. PuoTocARDiA iiii,i,Ai^A, Ii. Dit'schev. Zeitsehr. d. doutsch. geol. Gesellsch., 

vol. XV, p. 346, 

1864. Cahdium (Pkotucardia) Hillana, K. A. Zittel. DieBivalv. d. Gosaiigeb., 

I, p. 42 [146], pi. vii, figs. 1, 2. 
1866. — lliiji.XNVM, F. J. Pidet and G. Ciiinpiche. Terr. Cret. Ste. Croix 

(Mater. Pal. Suisse, ser. 4), 
pi.. 268. 273. 
? 1867. — — 0. Fniiit!. Alls d< m Orient, I, p. 91. 

— — — E. GuiJraiiijcr. Allmiu I'ak'oiit. de la Sartlie, p. 16, 

pi. XX, figs. 3, 11. 
I86a. — — A. Briait and F. L. Cornet. Meule de Bracqueguies 

(Mem. eour. et Mem. des Sav. ctraugers, • 
vol. xxxiv), p. 66, pi. vii, figs. 4, 5. 
1870. PuuTocAKDiA HiLLANA, F. Uumef. Geol. v. Oberschles., p. 334, pi. xxvi, 

fig. 2. 
? lS71. Pkotucakdium Hillanum, F. Stoliczka. Palaeoiit. Indiea, Cret. Fauua S. 

India, vol. iii, pp. 209, 219, pi. xii, 
figs. 8 — 10, pi. xiii, figs. 1 — 3. 
1873. — — II. Ii. Geinitz. Das Eibthalgeb. in Sacbseu 

(Piilieontogr.ipbiea, vol. xx, 
pt. i), p. 230, pi. 1, figs. 11,12. 

— Cardium — var. moabiticum, L. Lariet. Ann. Sci. geol., 

vol. iii, p. 53, pi. xii, fig. 9. 

1876. Pkotocakdia Hillana, D. Brauns. Zeitsehr. f. d. gesammt. Naturwiss., 

vol. xlvi, p. 266. 

1877. Protocardium Hillanum, .1. Fritach. Stud, im Gebiete der bolim. Kreide- 

t'crmat., ii,Weisseuberg. u.Maluitz. 
SeLiieht., p. 112, fig. 64. 



PROTOCARDIA. 199 

? 1878. Protocardium Hili,anuivt, 0. Fraaf:. Ans deiii Orient. II Geol. Beobacht. 

am Libanon, p. 70. 
1882. Cardium (Protocardium) Hillanum, P. de Loriol. Gault Je Cosne, p. 

69, pi. Tiii, fig. 17. 
1884. Protocardium Hillanum, /. F. Whiteaves. Mesoz. Foss. (Geol. Surv. 

Canada), vol. i, p. 228, 
pi. XXX, fig. 5. 
P — Cardium (Protocardia) Hillanum, C. E. Hamlin. Mem. Mus. Comp. 

Zool., vol X, No. 3, p. 50. 
1893. Protocardium Y{ua,,\nvm, R. Michael. Zeitschr. d.deutsch.geol.Gesellsch., 

vol. xlv, p. 232. 

1897. — — A.Fritscli. Stud, im Gebietederbolim. Kreide- 

format., vi, Chlomek. Schicht., 
p. 52. 

— — — B,. Leonhard. Kreidef. in Oberscbles. (Pal- 

OBontograpliica, vol. xliv), p. 28. 

1898. — — A.Fritsch. Stud, im Gebieteder bobm. Kreide- 

format., iii, Iserschicht., p. 98. 

1901. Protocardia Hillana, F. Slnrm. Jabib. d. k. pieussisch. geol. Landes- 

anst. fiir 1900, vol. xxi, p. 79. 

1902. — — A. Quaas. Kreidebild. in der libysch. Wiiste 

(Palseontograpbica, vol. sxx, 2), 
p. 218, pi. xxiv, fig. 18. 
1904. — — B.. Fortnu. Bull. Instit. Egyptien, ser. 4, no. 4, 

p. 331. 

— — — var. UMKWEI.ANENSIS, R. Etheridge, jun. Second 

Rep. Geol. Surv. Natal and 
Zululand, p. 79, pi. i, fig. 16. 
1906. — — xdi:, H. Woods. Cret. Fauna of Pondolaud (Ann. 

S. African Mus., vol. iv), p. 3(i7, 
pi. xxxvii, fig. 6. 

Deacriptiov . — Slioll convex, with flattened posterior slope, nenrlj- equilateral ; 
outline more or Ic.-^s .suli-iiuadrate, rounded, .*ioinetimes ncarl}' oval; usually a 
little higher than long, but raivly with the height and length erpial Anterior 
margin eitliei- fairly conve.x and forming a rounded angle with the antero-dorsal 
margin, or very convex and passing almost gradually into the antero-dorsal 
margin. Anterior margin passes gradually into the ventral mai-gin, which may be 
considerably convex, but is usually only slightly convex, with its posterior part 
nearly straight and forming a more or less well-marked angle with the posterior 
margin. The latter is truncated, slightly convex, and forms an obtuse angle with 
the postero-dorsal margin. Umbones of moderate size. 

Ornamentation consists (except on the posterior part of the shell) of junnerons, 
very regular, rounded, concentric ribs separated by narrow furrows; these ribs 
become smaller or nearly obsolete near the antero-dorsal margin. On the posterior 



200 CRETACEOUS LAMELLIBRANCHIA. 

slope of the shell, ;md soiiietiuies for a short distance in front of it, are from lU to 1-j 
(usually 12 or 13) strong, more or less angular ribs, separated by broad furrows, 
both being crossed by well-marked growth-ridges. Sometimes some of these ribs 
are divided at their summits by a narrow, longitudinal groove. The ribs become 
rather smaller dorsally and are absent near the postero-dorsal margin. Internal 
margins of valves smooth, except the ])ostcrior jiai-t with radial I'ibs, which is 
serrate. 



easwemenfs : 
















(1) 


(a) 


(:*) 


(0 (.r,) (0) (7) (s) 


(9) 


(10) 


(11) 


(12) 


Length 51 


48 


44 


44 43 41 38 36 


36 


32 


27 


19 mm 


Height 47 


47 


44 


42 41 39 36 36 

(1—12) Black-down. 


34 


29-5 


26 


18 „ 



Affinities. — Although this species has a very wide geographical distribution 
and a long range in time, yet the principal variations seen in specimens found 
at different horizons and in different kinds of sediment consist in the number and 
coarseness of the concentric ribs. The modifications do not appear to Ijc more 
than varietal, and such as would be found at the present day in examples of a widely 
distributed species. 

In the example from the Cenoraanian figured by d'Orbigny the shell is i"ather 
higher and the ornamentation coarser than in specimens from Blackdown, but in 
the latter respect it agrees with examples found by the late C. J. A. Meyer in the 
Cenomanian of Soiith Devon. One specimen from the Cenomanian of Sarthc, 
shown in Gueranger's photographic illustrations, agrees in its ornamentation with 
Blackdown examples. 

The Cenomanian form figui'ed by Romer (1870), and the examples from 
higher horizons figured by Geinitz (1843) and by Goldfuss agree closely with Black- 
down specimens. Coarser ribbing is found in specimens from the Gault of Cosne, 
showing that that character is not limited to examples from horizons above the 
Blackdown Greensand. 

Protocar(Jia hifrons (Reuss) is more rounded than P. Ilillana, but does not seem 
to be specifically distinct. 

Gdvdium mnrticense, Matheron, and ('. llequienianum, Matheron, were regarded 
by d'Orbigny and by Zittel as synonyms of P. Ilillana. 

Specimens from the Trichinopoli Group of Soutliern India weir identified with 
]\ Ilillana by Forbes and by Stoliczka, who stated that they were unable to draw 
any line of separation between the Indian and Kui-opean examples. Tlu> concen- 
tric ribbing is coarser in most of the Indian forms, and in some the smooth inner 
portion of the posterior area is relatively larger than in specinuMis from Blackdown.' 

• Sec Stoliczka's fif,'. I0,r. 



CARDIUM. 201 

P. dellcatula, Stoliczka/ and P. pondicheriensr (d'Orhigny),^ are allied to 
P. Hillana. 

P. hiseriatii ((Jonrad),'^ from Syria, possesses coarse concentric ribs, and is 
regarded by Blanckenhorn as a variety of P. Hillana. 

BemarlcH. — Examples of this species are common at Blackdown, but probal)ly on 
account of the uniformity of the conditions under wliich they lived, do not show 
any very striking variations. 

There are some differences in the proportion of length and height ; usually the 
former exceeds the latter slightly, ])ut occasionally the two are equal. The outline 
of the shell is sometimes oval, but more usually subquadrate. The radial ribs vary 
in number from 10 to 15, and sometimes the area with these ribs is continued for a 
short distance in front of the posterior slope. 

The number of concentric ril)s in 10 mm. (measured between 34 mm. and 
44 mm. from the umbo) varies from 15 to 19. 

Tiipe. — From Blackdown, in the British Museum. 

Disfrihution. — Upper Greensand (zone of Schhvnhacliia. rostrata) of Blackdown, 
Haldon, Whitecliff (South Devon), I'eak Hill near Sidmouth, Devizes, and 
Ventnor. Cenomanian of Dunscoinlie. Recorded by .Jukes-Browne from the 
Chloritic Marl of the Isle of Wight. 

Genus — Cakdium, f/iiui,rus. 
('Syst. Nat.,' ed. 10, 1758, i.. 678; ed. 12, 17GG, p. 1121.) 

Cardium Ibbetsoni, Forbes, 1845. Plate XXXII, figs. 7 — 10. 

1845. Cardiijm Ibbetsoni, E. Forbes. Quart. Jouin. Geol. Soc, vol. i. p. 243, 

pi. ii, fig. 9. 
1854. — — J. Morris. Cat. Brit. Fo§s., ed. 2, p. Ut2. 

1856. — — F. J. riiirl and E. Beuevier. Foss. Terr. Aptien 

(Mater. Pal. Suisse, ser. 1), p. 78, 
pi. ix, figs. 1, 2. 
1866. — — F. J. Pirtel and G. Campiche. Terr. Crct. Ste. Croix 

(Matc'r. Pal. Suisse, ser. 4), 
p. 262. 
1871. — — {ItMyicKnmvM), F. Stoliczka. Pateout. ludica, Cret. 

Fauna S. India, vol. iii, p. 213. 

I 'PahcDiit. Indiea, Cret. Fauna S. India,' vol. iii (1871), ]). 220, pi. xiii, fig. 8. 

- St.diczka, ibid., p. 220, pi. xii, figs. 4—7. 

3 ' Official Report U. S. Exped. Dead Sea, etc.,' by W. F. Lynch (1852), p. 216, pi. vi, figs. 38, 39 
(non 40); R. B. Newton, 'Geol. Mag.,' (1898), p. 40t1, jd. xv, fig. 11. F. Hillana var. lypica, 
M. Blanckenhorn, 'Beitr. zur Geol. Syriens : Kreidesyst. in Mittel u. Nord-Syrieus ' (1890), p. 89. 



202 CRETACEOITS LAMELLTBRANCHTA. 

JJrsrripfinu. — Shell siuall, inflated, oval, a little higher than long, slightly 
inecjuilateral. Anterior margin rounded, passing gradually into the convex 
ventral margin. Posterior margin sul^truncate, higher than the anterior margin. 
UmVwnes prominent, with a faint carina extending to the postero- ventral extremity 
and forming tlu^ limit of the flattened postero-dorsal area. Margins of valves 
serrate. 

Ornamentation consists of numerous small, slightly-raised radial ribs separated 
by narrow grooves ; anteriorly the ribs become gradually smaller and are absent 
or indistinct near the antei'o-dorsal margin ; on the postero-dorsal area the ribs 
are stronger and the grooves broader than elsewhere, and the anterior margins of 
these ribs are sometimes serrate. In Avell-preserved specimens faint concentric 
linear ridges are seen. 

Meafnimnrvfa : 

(1) (2) (3) 



(4) 


(5) 


14 


1 (>•-") mm 


14-5 . 


11 „ 



Length .17 . 15-5 . 14-2 . 
Height .18 . 16-5 . 15 

(1—5) Crackers. AthertieUl. 

Affiuifirs.—iiec G. GuttaUmnm (p. 203). 

In form C. Ibbetsoni resembles 0. Banliniannm, d'Orbigny,^ but the latter is 
distinguished by its broader grooves which bear pointed projections.- 

In the specimens figured by Pictet and Renevier from the Aptian of the Perte 
du Rhone the umbones are more prominent than in English examples of 
0. Ihhdsoni, but Pictet and Campiche, who were able to compare examples from 
Atherfield with those obtained from the Perte da Rhone, felt no doubt as to 
their specific identity. 

Ti/pe. — From Atherfield, iu the Museum of the Geological Society. 

Distribution. — Lower Grreensand (Crackers) of Atherfield. 

' -Pill. Frauv- Terr. Cn't.,' vol. iii (1844j, p. 25. pi. cc-xlii, fi.i,'s. 7—11. 

' C. Bauliniannm is rocorJed by Morris from the Lower Greensaml nt' t ln' Isle of Wight, aud by 
Topley from the Atherlield Beds of Peasmarsh and Shalfonl. Specimens from the Atherfiehl Clay 
wei-e referred to C. suhhUlaimm, Leymerie, by Forbes, but that identilication was regarded as doubtful 
by Pictet and Campiche ; the form of the shell cannot be made out satisfactorily, but the ornamenta- 
tion resembles that of G. Ibbetsoni. Au internal cast from the Lower Grreensand of Upware was 
referred with doubt to C. unhhillaitnin by W. Keeping (' Foss. Neoc. Upware and Brickhill,' 1883, 
p. 119) ; the specimen is now in the Sedgwick Museum, Cambridge, and seems to me insufficient 
for determination. A specimen with radial ribs, from the Lower G-reensand of Maidstone, was named 
CartJium Bemtedi by Forbes, but was too imi)erfect for figuring ; the type is in the Museum of the 
Geological Society (No. 2124) ; no other specimen has been seen. Forbes, 'Quart. Jouru. Geol. Soc.,' 
vol. i (184.5), p. 244 ; Pictet and Canii)ichc, ' Foss. Terr. Cn't. Ste. Croix ' (' Mater. I'al. Suisse,' ser 4, 
186G). p. 267. 



CARDIUM. 203 



Cakuium Cottaijunum, (CUrbhjiuj, J 8-14. Plato \XX1I, tig. 11 a — n. 

1844. Cakdium CoTTALDiNUM, A. d' O fhlij II ij . Pal. Frauy. Terr. Civt., vol. iii, 

p. 22, pi. cc.xlii, figs. 1 — 4. 

1850. — — d'OrhUjiiij. Pi-odr. de Pal., vol. ii, p. 79. 

1866. — • — /''. /. Pictet and G. Campiche. Terr. Crut. Stu. 

Croix (Mater. Pal. Suisse, ser. 4), 
p. 246, pi. cxviii, figs. 1, 2. 
1871. — — F. StoUczka. Palseont. ludica, Cret. Fauna 8. 

India, vol. iii, p. 212. 
1S83, — — W. Keepimj. Foss., etc., Neoc. Ui^ware and Brick- 

hill, p. 118, pi. vi, fig. 4. 
1884. — — O.Weerth. Die Fauna des Neocom. im Teutoburg. 

Walde (Palreout. Abhandl., vol. ii), 
p. 44, pi. ix, fig. 3. 
— — Obrlinghusanum, Weerth. Ibid., p. 44, pi. ix, fig. 4. 

1895. — CoTTALDiNDM, G. Matts. Zeitscbr. der deutsch. geol. Gesellsch., 

vol. xlvii, p. 263, pi. vii, figs. 2, 3. 
1900. — — A. Wollemanii. Die Biv. u. Gastrop. d. deutsch. u. 

liolliiud. Neocoms (Abhandl. d. 
k. preussiseh. geol. Laud., n. f., 
pt. 31), p. 107. 

Descrlptidii. — Shell oval, inflated, sligiitly iiu'nuilateral, rather higliex" than long. 

Anterior autl ventral margins rounded. Posterior margin more or less truncated. 

Umbones rather high, sharp, curved inward and forward, with an indistinct carina. 

Ornamentation consists of numerous, small, regular, radial riljs, which are 

rather more proiuinent on the posterior area than on the sides of the shell. 

Measurenieiifs : 

Length .... 24' mm. 

Height .... 25"5 „ 

Upware. 

Alfiiiifies. — This species closely resembles C. Iljhctsuiil, Ijut iliffers in having the 
posterior area less flattened and the outline of the shell more rounded. The 
English specimens of G. Cuttaldinuin are larger than those of G. Ibhelsoui, but are 
not sufficiently numei'ous oi' well-preserved for exact comparison. 

In C. Guttaldinum the shell is relatively higher than in (/'. Voltzi, Leymerie.' 

G. laiideronense, de Loriol," appears to be closely i-elated to G. Guttaldinum. 

Type. — D'Orbigny's specimens came from the Neocomian of Wassy (Ilaute- 

' For references see Pictet and Campiche, ' Terr. Crct. Ste. Croix ' (' Mater. Pal. Suisse,' ser. 4, 
1866). p. 247. 

- P. de Loriol aud V. Gillicrou, • Urgouieu luicr. dc Lauderou ' (1869), p. 14, pi. i, fig. 12. 



204 CRETACEOUS LAMELLIBRANCHIA. 

Mai'ne), Brilloii (Mouse), St. Sauveur and Auxerre (Yonue). The specimens 
figured hy Keeping are in the Sedgwick Museum. 
Distribution. — Lower Greensand of Up ware. ^ 



Caediuji, s]). Plate XXXII, fig. 12 a, h. 

Internal casts of a globose form of (Jarduiiii occur in tlie Lower Greensand of 
Seend and Faiingdon. On one specimen (No. 21272, Museum of Practical 
Geology) a portion of the shell is (ii'eserved, and its oi-nanientation resembles that 
of G. Ihhetsoiii and G. Cottaldinuin. The form of tlie shell seems to l)e rathei- more 
like that of (J. llihctsonl than of G. Gotlaldiinini. 



Cabdium, spp. 

Specimens of Gnrdlinu from the Cenomanian of Dunscombe, South Devon, were 
referred by C. J. A. Meyer to G. alternans, Reuss, and G. alufacemn, Goldfuss. 
Better preserved specimens are needed before these determinations can be con- 
firmed. 



Cahdium turuniknse, WouJh, 1SV)7. Plate XXXII, figs, lo — 15. 

1897. Cakdium TUKoNiEN.SE, i/. Wooils. Quart. Jouiu. Geol. Soc, Vol. liii, p. 389, 

pi. xxvii, figs. 20-22. 

Description. — Shell small, oval, higher than long, incMjuilateral, much inflated, 
postero-dorsal part compressed. Umbones prominent, with a considerable anterior 
curvatui'e. Ornamentation consists of many strong radial ribs. Length, (imni.; 
height, 7 mm. 

Ajjinitles. — This species shows some resemblance to ('. o'/M'/z/ffHcz/sc, d'Orbigny,- 
but is more inequilatei'al owing to the much greater curvature of the umbones ; 
also the ribs are less numerous, and tubercles appear to be absent from tln^ 
grooves. 

Type. — In the Sedgwick Museum, Cambridge. 

Distribitfioii. — Chalk Rock of Cuckhamsley. 

1 Some small specimens found iu the Ferruginous Sands of Slianklin may perhaps be referred to 
C. CollahUnnm, but they are too imperfeelly preserved for exact determination. 
- 'Pal. Frauy. Terr. CrJt.,' vol. iii (1844), p. 37, pi. ecxiix, figs. 5—9. 



CARDIUM. 205 

Oardium, sp. Plate XXXII, fig. IG a, b. 

1897. Cardium, sp. cf. cenomanense, H. Wooih. Quart. Joiini. Geol. Soc-., vol. 

liii, p. 38i), pi. xxvii, tigs. 23, 24. 

Intoi'nal casts, similar in form to G. cenomanense, d'Orbigiiy, are found in the 
Chalk Rock of Cuckhamsley. A part of the shell is imperfectly preserved on one 
specimen and is ornamented with fine radial ribs. A cast measures : height, 8 mm.; 
length, 8 mm.; thickness, 7"5 mm. 



Caudium, sp. Plate XXXII, fig. 17 a—c. 

Two internal casts from the Chalk of Norwich (one of which was found by the 
late T. G. Bayfield) are in the British Museum (Nos. L 19443, L20lUo). The shell 
is much inflated, so that the height and thickness are approximately etjual ; the 
height is considerably greater than the length. The unibones are prominent. 
The postero-dorsal part of the shell is flattened and shows indications of fine radial 
ribs. 

This species shows some resemblance to G. venivlcusain, d'Orbigny,' but is 
relatively higher. 

Stili-ijcuiis — Gkanucakuium, ir. .1/. (Iiilili, 18G9. 
(" Geul. Survey Calit'uruiii," ' I'aliuout.,' vol. ii, p. 20G.) 

* 

Caedium (Geanocaruium) I'KdiJusciDEUM, Soiverbij, 1817. Plate XXXII, figs. 18, 19; 

PlateXXXIII,figs. 1 — 3. 

181G. Cakuita tuhkkculata, J. Sowcrby. Miu. Coiuli., vol. ii, i>. 1(7, pi. u.\liii. 

(Non Cardium tuhercuhiinm, Liunaus). 
1817. Cardium pkoboscideum, J. Smrerbi/. Min. Couch., vol. ii, p. 127, ])1. clvi, 

%• 1- 
1835. — Gentian UM, J. i/e C «'5'((»'«/&y. Ibid. (Systematical ludex), vol. vi, 

p. 242. 
1854. — PBOBOSCIDEUM, /. Morris. Cat. Brit. Foss., eJ. 2, p. 193. 

— — Gentianum, Morria. ibid., p. 192. 

1866. - PROBOSCIDEUM, /•'. ./. Pirti't and G. Catnpiche. Foss. Terr. Crt't. 

Ste. Croix (Mater. Pal. Suisse, 
ser. 4), p. 269. 

1 G. ventricosum is recorded from the Upper Greensand (zone of Pecten asper) of Lulworth by 

Barrois ('Terr. Cit't. Super, de rAuglotrrre et de I'ln-laiulc,' 187<;. ji. 02). I have not .seen any 
English example of tliat species. 

27 



2UG CHKTACEUU8 LAMEI;L1BRA^XM1IA. 

I80(j. CaIvUIUM CJentianum, Pldd and Camplche. iliid., p. 2G9. 
1871. — PEOBOSCIDEUM, F. StoUczka. Palseont. ludica, Grot. FLUiiia S. 

India, vol. iii, p. 213 {Acatdho- 
cardinm). 
— — Gentianum, StoUczJca. Ibid., p. 213 {Acanthocardium). 

1882. — PEouosciDEUM, P. de Loriul, Gault de Cosue, p. 91, pi. xi, tig. 4. 

1900. — Gentianum, E. T. Newton and A. J. Jukes-Browne. lu Jukes- 

Bi'owue, Cret. Rocks of Britain, 
vol. i, p. 448. 

Descrijifhin. — Sliell stout, very convex, ovul, higher than long, slightly inequi- 
lateral. Anterior margin rounded ; posterior margin truncated, forming an 
angle with the po.stero-dorsal margin. Unil)ones prominent. 

Ornamentation consists of radial ribs separated Ij}- narro^Y grooves ; the 
stronger ribs bear prominent, angular, laterally compressed tooth-like ))rojections, 
which may be rather larger near the posterior margin than elsewhere ; in the 
spaces between the stronger ribs are two (sometimes one or three) smaller ribs with 
similar but smaller tooth-like projections. Margins of valves toothed. 

Measurements : 

(1) (2) (3) 

Length G3 . 59 . 58 

Height 74 . 7*t . 68 

(1—5) Blackdowu. 

Affinities. — A form from the Cenomanian was referred l)y d'Orbigny to 
C. pwdnrtum, Sowerby,^ the type of which comes from the Senonian of Gosau. 
Tliis identification has been accepted by Zittel, Holzapfel and others, but not by 
Pictet and Campiche, and de Loriol. The specimen figured by d'Orbigny - is 
probably an example of G. fvohoscideum, Sowerby, and differs from G. prothidum 
in the distinct differentiation of the ribs into a larger series separated by smaller 
series. 

The differences between G. Gentiamun and C. prohosc'ideum seem to be due 
entirely to their different modes of preservation. The former is found in the 
Upper Greensand of Devizes and Ventnor; the shell is absent, but the sand whicli 
filled the interior of the shell now forms a natural cast of the exterior, showing 
more or less imperfectly the character of the ornamentation ; usually the spines 
are represented l)y stumps only or are almost completely obliterated. In these 
specimens the original form of the shell has been more or less considerably 

• 'Trans. Geol. Soc.,' ser. 2, vol. iii (1832), p. 417, pi. xxxix, fig. 15 ; Goldfuss, * Petref. Germ.,' 
vol. ii (1837), p. 221, pi. cxliv, fig. 7 ; Zittel, ' Bivalv. d. Gosaugeb.,' pt. i (1864), j). 37, pi. vi, fig. 1 ; 
Holzapfel, "Die Mollusk. Aachen. Kreide " (' Palaeontographica,' vol. xxxv),p. 179, pi. xvii, figs. 1 — 5; 
G. Miillcr, 'Mollusk. d. Uutersen. v. Braunscliweig u. Ilsede ' (1898), p. (33, pi. ix, figs. 13, 14. 

- ' Pal. Frany. Ti'rr. Cret.,' vol. iii (1844), p. 31, pi i-cxlvii ; Gucranger, ' Album Pak'ont. du la 
Sarlhe ' (1867), p. 15, pi. xx, tigs. 8—10. 



(4) 


(5) 


57 


47 mm 


65 


54 „ 



TOUCASIA. 207 

modifitMl l)y pressure. On tlie otlici- hand flic slicll in C. proboKciilniui, from 
Blackdown, is replaced by siliea, so that both its oniaiiiciifation and ori^-innl shape 
are perfectly preserved. 

French examples were idontitied by tl'Orbigny ' with this species, for which he 
proposed the name Canliam Moufonianvm since the specific name (tuberculafn) 
under which Sowerby originally described the species had already been used. 
Sowerby, however, in the index at the end of vol. vi of the 'Mineral Conchology,' 
had already substituted Gentianum for the name which he originally used. I have 
not seen an}' specimen of C. Motitoninnmn, and am unable to say whether or not it 
is really identical with G. Gcntlnnnm, but in d'Orbigny's figures the difference in 
the sizes of the ribs and tubercles is seen on the anterior and posterior parts of 
the shell only. 

G. GaroUnvm, d'Orbigny,^ and G.incequicostatnm, Matheron,^ are closely related 
to, and perhaps identical with, G. pnihoscidpnm. 

T;/i>cs. — G. j)rohoscidet(,m, from the Upper Greensand of Blackdown, and 
Garditii tnhcrcuJata (Gardium Gentianum), from the Upper Greensand of Devizes, 
are in the British Museum. 

DiMrihntlon. — Upper Greensand (zone of Schlnmhachia rosfrata) of Blackdown, 
Haldon, Devizes, and Ventnor. 



Famihj—BlCE'RkTl'DJE, Thill. 
Genus — ToDCASiA, E. Munior-Ghulmnft, 1873. 

(' Jonm. (le Concliyl.,' ser. 3, vol. xxi, p. 74. Douville, ' Bull. Soc. gc'ol. de France,' ser. .3, vol. xv, 

1887, p. 762.) 



ToucASiA LoNSDALEi {Sowevhy), 183G. Plate XXXIII, figs. [■ — G. 

1836. DiCKRAS LoNSDALii, .7. (le C. Soiverhy. Trans. Geol. Soc, ser. 2, vol. iv, 

pp. 268, 338, pi. xiii, fii?. 4. 
1850. Capeotina Lonsdalii, A. d'Orhitjinj. ProJr. de Pal., vol. ii, p. 109 

(parti III). 

1854. Diceeas Lonsdalii, J. Morris. Cat. Brit. Foss., ed. 2, p. 201. 

1855. Requienia Lonsdalei, S. P. Woodward. Quart. Jouru. Geol. Soc., 

vol. xi, p. 53, fig. 29. 
1871. — Lonsdai.ii, F. Stoliczt:a. Palseont. ludica, Cret. Fauna 

S. India, vol. iii, p. 233. 

» ' Pal. Fran9. Terr. Cret.,' vol. iii (1844), p. 34, pi. ccxlviii ; and ' Prodr. de Pal.,' vol. ii (1850), 
p. 162. 

- Op. cit. (1844), p. 29, pi. fcxlv. 

* ' Catal. Foss. des Boucli.'s-du-Rlione ' (1842), y. 157, pi. xviii, figs. 3, 4. 



208 CRETACEOUS LAMELLIBRANCHTA. 

Bemarks. — The examjiles of Toucasia Lonsdalei are m the condition of internal 
casts in a ferruginous sandstone, so that it is difficult to compare this with other 
species. The casts show a considerable amount of variation in form. D'Orbigny, 
de Loriol, and Pictet and Campiche included Bcquienia carinata, Matheron,' from 
the Urgonian of Orgon, as a sj'nonym of Sowerby's DIceras Lonsdalei; but Prof. 
Douville- and M. Paquier^ think that the identity of the two forms is doubtful 
and can only be determined by a careful comparison of English specimens witli 
internal casts of T. cnrinnta. Prof. Douville *^ suggests that there is a resemblance 
between T. Seunesi and T. Lonsdalei. 

Type. — The type, which is stated to have come from near Calne, cannot now 
be found. The specimen from which Woodward's outline figure was drawn is in 
the British Museum, No. 88825. 

DlstriliKtion. — Lower Greensaud of Stock Orchard, south of Calne. Recorded 
by Morris from Lockswell Heath, south-west of Calne. 



Famil ij— MO^OFhFAmiBJE, Fischer. 
Genus — Gyropleura, 7/. Ihnirdl', 1887. 

('Bull. Soc. gt'ol. (le France,' ser. 3, vol. xv, p. 7()8.) 



GYRorLEUifA coRNUCopi.K {d'Orhiijii //), 1847. Plate XXXIII, fig. 7 a, Ik 

1847. Chama coRNUoopiiE, A. J'Orhujny. Pal. Fniuc. Terr. Cret., vol. iii, p. 689, 

pi. cecclxiv, figs. 3 — 7. 
18r,0. — — tl'Orhicjny. Prodr. (le Pal, vol. ii, p. 170. 

1 808. — — F. J. Pictet and G. Campiche. Terr. Crut. do Ste. Croix 

(Mati'r. Pal. Suisse, ser. 5), p. 7. 
1871. — — F. Htoliczlca. Paloeout. ludica, Cret. Faima S. India, 

vol. iii, p. 234. 
1887. Gyropleura — //. Douville. Bull. Soc. jjfrol. de France, ser. 3, vol. 

XV, p. 771, fig. 3. 

Bemnvls. — ^^vo s]K'ciniens rroui llic Clilorit ic i\I;ii'l of Dorset agree in i'onu 
with e.\aiuj)le.<i of (!. cornucoina.' from tlie Cenomanian of Houen (the locality 

1 ' Catal. Foss. des Bouclics-du-Ilhoiie' (1842). p. U)4, pi. ii, figs. 1,2; Cajirotina Lonsdalii, 
d'Orbiguy, ' Auu. Sci. Nat. Zool.,' ser. 2, vol. xvii (1842), j). 180; liecpiienia Lonsdalii, d'Orbiguv, 
'Pal. Franc. Terr. Crot.,' vol. iv (18.50), p. 248, pis. dlxxvi, dlxxvii ; Caprvlinn Lonsdalii, de Loriol, in 
Favrc, ' Rcch. gi'ol. dans Savoio,' vol. i (18()7), p. 38(i, pi. C, fig. 22; licfjuicnla Ldn.^dalii, Pictot and 
Campiche, 'Terr. Cri't. Ste. Croix' ('Mater. Pal. Suisse,' ser. 5, 1868). p. 14, pi. clxi. 

2 'Bull. Soc. gcol. de Franco,' ser. 3, vol. xvii (188!»), p. 630. 

^ 'Les Rudistcs Urgouieus,' I (' Mrin. Soc. gi'ol. de France,' i'aK'out. XI, 11)03), p. 41. 
* Op. cit., p. 632. 



GYROPLEURA. 209 

of the type) and with d'Orbigny's figs. 4 and 5. The ornamentation in this 
species is imperfectly known ; most of the examples from Ronen are either 
internal casts or have only portions of the shell present, on which the orna- 
mentation is rather indistinct. In one specimen from Dorset part of the shell 
of the fixed valve is preserved ; the radial ribs are not so prominent as in 
Ct. ivpijiiiroKh-iifd, ])ut concentric lamellte are distinct. 

Distribiifinn. — Chloritic Marl of Melbury Park and Chaldon, Dorset. Recorded 
by Jnkes-Browne from the base of the Lower Chalk of C'liard and Maiden 
Newton. 



GYRorLEURA INEQUIROSTRATA {Wondivard), 1 880. Plate XXXIII, figs. 8 — 13. 

1833. DiCERAS iNEQUiRosTRATus, S. Wondivard. Geol. Norfolk, p. 47, pi. v, fig. 22. 
1854. Chama in.«quirostrata, J. Morris. Cat. Brit. Foss., ed. 2, p. 194. 

Description. — Shell nmch inflated. Right valve large, oval, attached by a 
considerable portion of the anterior side; nmho prominent, pointed, incurved 
anteriorly. Left valve capuliform, with the umbo near the hinge-margin. 

Ornamentation consists of strong, lamellar radial ribs, which are undulose 
where they cross growth-i'ings. The ribs have strongly serrate summits and 
are separated by rather broad, flat, smooth interspaces ; sometimes the serrations 
are replaced by iininerons transverse, scale-like structures. Near the fixed part 
of the ri<j;ht valve the ribs are more numerous than on the flank. 

Measirremeids of fixed value. : 

(1) (2) 

Length . . 22 . ID 

Height . .28 . 2(5 

(1 — 4) Norwich. 
AJfinifie!<. — G. rijili/aiia (dc Ryckholt),' from Ciply, differs from this species 
in having the ribs more widely separated and in the presence of small ribs in 
the inter.spaces and on the sides of the main ribs. CI. rn.'isiensi.v (d'Orbigny)- 
i-eseml)les closely G. ineqnirostrata and was regarded by Morris as a synonym of 
the hittei-, but it possesses small ribs on the sides of the main ribs.^ 

1 ' Mi'laii-es Tak-uut.," pt. ii (18.51), p. 179, pi. xii, %s. 12, 13; Douvilk', 'Bull. Soc. gc'ol. de 
Fniuce,' ser. 3, vol. xv (1887), p. 744, pi. xxviii, fig. 11 ; Holzapfel, ' Mollusk. Aachen. Kreide ' (1889), 
p. 189, pi. xix, figs. 5, 6; Wollemanu, ' Fauua d. Liiuelmrg. Kreide' (1902), p. 75, pi. ii, figs. 5, 6. 

- Murehisou, de Vernciiil, and de Keyserliug, ' Gcol. do la Kussie,' vol. ii (1845), p. 49(j, pi. xliii, 
figs. 31—33 ; Douvilk', 'Bull. Soc. gc'ol. de France,' ser. iii, vol. xv (1887), p. 775, pi. xxviii, fig. 13. 

» G. Miinsteri (v. Hagenow) is probably related to O. hmqmrontrala. See Kavii, ' MoUuslc. i 
Daniuarlis Kr.-idtafl. I. Laiiullibr.' (1902). p. 12(5, pi. iv, figs. 10, 11. 



(3) 


(4) 


16 


14 mm. 


20 


18 „ 



210 CRETACEOUS LAMELLIBRANCITIA. 

Type.— From Norwich; in tiie Jiritish Museum. 

Distrihution. — Upper C-lialk (zone of Iklemnitdla mucronalu) of Norwich. 



GvKoi'i.KTUA, sp. Plate XXXIV, fig. 1 a — d. 

Ih'xcri plioii. — Iiiti'ht valve inflated, attnehcd \)\ a lar^'e poi'tioii of the dorsal 
surface. Left valve convex, subcjuadrate, with a ])ointed tind incni'ved und)o. 
Rinht valve ornamented with numerous, small radial ril)s which bear transverse 
nodes or scales. Left valve with relatively few, stout ribs bearing strong, some- 
what irregular, transver.so scales or lappet-like projections. 

AJfinifM's. — The ornamentation on the right valve is finer and that on the left 
valve coarser than in G.cenomannisis (d'Orljigny ') ; also the t ransverse ornamenta- 
tion of the ribs is much coarser and less regular.- 

Bemarkti. — The portion of the right valve which was attached includes the 
umbo and the neighbouring parts, whereas in most examples of Oyroplenra only 
the part in front of the umbo is attached. The size of the area which was attached 
is larger than usual, but in other s]iocies it is seen that that area varies consideral)ly 
in size in different examples.^ 

The only specimen seen was collected liy Mr. Francis R. B. Williams. 

Disti-il)iifin]i. — LTpper Chalk (zone of Actinocamax quadra Iiik) near the groyne 
at Seaford. 



F«.miZ?/— CORBULID^, Fleming. 

Genus — CoRUULA, /. G. Ihnguiire, 1707. 
(' Encyc. Mt'tb.,' Tabl. Vers., pi. 230.) 



Cnnnt'LA ANOur.ATA (rhillip^), 1820. Blate XXXIV, figs. 2—5. 

1829. IsocARDiA ANGULATA, J. Phillipn. Gcol. Yorks., p. 94, pi. ii, fiiis. 20, 21 

(ed. 3, 1875, p. 252). 
1841. — _ p. ^. Burner. Die Versteiu. d. uord - deutsch. 

Kreidegeb., p. 70. 
1854. — —J. Morris. Cat. Brit. Foss., ed. 2, p. 204. 



1 ' Pal. Fraiu;, Terr. Cn't.,' vol. iv (1850), p. 261, pi. dxcv, fiii;s. 1—4. 

2 Douvilk', 'Bull. Soc. grol. do France,' ser. 3, vol. xv (1887). p. 771, pi. xxviii, fit;. 7. 

■'' In a specimen figured by Griepeukerl tbe surface of attacbmeut is unusually large ; ' Senon v. 
Kimigsluttor ' ('Palseont. Abliaudl.,' v, 1889), pi. vii, fig. 3. 



CORBULA. 211 

18t)5. IsooAKUiA? ANUULATA, F.J. Pictt't and G. Cuinpiche. Foss. Terr. Crct. Ste. 

Croix (Mater. Pal. Suisse, 
ser. 4), p. 240. 
1871. IsocARDiA ANGULATA, F. Staliczku. PaloGout. luJica, Cret. Fauua S. luclia, 

vol. iii, p. 194. 
1877. IsocARDiA ? ANGULATA, &'. iy'////)(. Zeitsclir. d. deutscli. geol. Gesellscb., 

vol. .xxix, p. 241. 
1889. IsocAKDiA ANGULATA, G. W. LampliKjli. Quart. Jo\u-u. Geol. Soc, vol. xlv, 

p. 616. 
1900. — — A. WoUemann. Die Biv. u. Gastrop. d. deutscli. u. 

bolliiud. Neocoms (Abliaudl. d. k. 
preussiscli. geol. Laud., N. P., pt. 
31), p. 114. 

1905. CoKBULA (Isocardia) AviovhAiA, E. Harhort. Fauua d. Seliaiunberg-Lippe- 

scbeu Kreidemulde (Ibid., 
pt. 45), p. 81. 

1906. Isocardia angulata, A. WoUemann. Die Biv. u. Gastrop. nord-deutsch. 

Gaults (Jabrb. d. k. preussiscb. 
geol. Laud., filr 1906, vol. xxvii), 
p. 277. 

Descrijjtioii. — Shell witli 8ul)-(]uadrate outline, rounded, occasionally sub- 
triangular, very convex, equivalve, more or less considerably inequilateral ; length 
greater than height. Anterior part produced, rounded ; ventral margin slightly 
curved ; posterior margin truncate, slightly convex, somewhat oblique, forming 
angles with the ventral and dorsal margins. Postero-dorsal margin sloping 
ventrally. Umbones moderately large, curved inward and more or less considerably 
forward, with a carina extending to the postero-ventral angle, cutting off a large, 
flattened postero-dor.sal area. The part of the valve in front uf the carina is 
regularly convex. Lunular region depressed. 

Ornamentation consists of fine concentric striae. 
Measarctiioits : 

(3) (-4) 

6-2 . G 
5-0 . 5 

(1 — 7) Speetou. 

Ajjiiiitii'.-i. — This species shows some resemblance to C. tjatilliiui (see p. 21 1), but 
is more nearly (juadrate in outline, relatively longer, of larger size, and without 
distinct ribs. 

G. aiKjulata is fairly common in the Speeton Clay, but no specimen showing the 
hinge appears to have l)een found, so that the generic position assigned to this 
species by Phillips was presumal)ly based on the external character of the shell. 
Pictet and Campiche thought that it probably belonged to Ci/jn-iiui. WoUemann 
states that it is most likely a Curiula, and Harbort, who has seen the hinge, 





(1) 


(^) 


Length 


. 7-1 . 


, G-8 


Height 


. G-U 


5'5 



(■') 


(fi) 


(7) 


G-0 . 


. 5-U 


. 4"5 mm 


4-.-> 


. 4-1 


. 1-0 „ 



212 CRETACEOUS LAMELLIBRANCHIA. 

(U'fiiiitely refers it to that genus; if this view of its position is confirmed it will be 
necessary to substitute a new name, since angulata had been previously used by 
Lamarck for a species of Gorhnla from the Eocene. 

Distribufdun. — Speeton Clay {'/.ones oi Belemnites jaculu in and //. hnnisviceims) 
of Speeton.^ 



CoKiJULA STIUATULA, S(jwcrhi/, 182/. I'kite XXXIV, tigs. G — 12. 

1827. COBBULA STKIATULA, J. dv C. Suivcvbij. Mm. Cuucli., Vol. vi, p. loi', pi. 

dlxxii, figs. 2, 3. 
1846. — —A. d'OrUynij. P;il. Fniuv- Ti-rr. Crt't., vol. iii, p. 459, 

pi. ccflxx.wiii, figs. 9 — 13. 
1850. — — A. d'Orhhjny. Prodr. do Pal., vol. ii, p. ILS. 

1854. — — /. Morris. Cat. Brit. Foss., ed. 2, p. 190. 

1868. — — F. J.PidelundE. Kcnevier. Toss. Terr. Aptieu (Mater. 

Pal. Suisse, ser. 1), p. 17(J. 
18(34. — — F. J. Piclet and G. Camjiiche. Foss. Terr. C'rct. Ste. 

Croix (Mati.'r. Pal. Suisse, ser. 4), 
p. 86. 
1870. — — F. Stoliczka. Palseout. ludica, Cret. Fauua S. ludia, 

vol. iii, J). 40. 
1895. — — • G. Maas. Zeitschr. der deutscli. geol. Gesellscb., vol. 

xlvii, p. 257. 
— — Ldivis, Maas. Ibid., p. 257. 

1900. — STRiATULA, A. Wollemaun. Die Biv. u. Crastrop. d. deutscli. u. 

holliiud. Neocoms (Abhaudl. d. k. 
preussisch. geol. Laud., N. F., pt. 
31), p. 144. 

Nou 1840. — — A. Goldfuss. Petref. Germ., vol. ii,p.251, pi. eli, fig. 16 

{C. siihsl rial Ida, d'Orbigny, 1850). 

— 1847. — —J. Miillcr. Petref. der AacLen. Kreidel'., pt. i, p. 25, 

pi. ii, fig. 8. 

— 1854. — — A. d'ArcJduc. Bull. Soc. geol. de France, ser. 2, vol. xi, 

p. 209, pi. iv, figs. 14, 15. 

— 1858. — — J. Vilanova-y-Piera. Mem. geog.-agric. de Castellou, 

pi. iii, fig. 14. 

— 1867. — — 0. Fraas. Aus dcm Orient, p. 92. 

— 1870. — — H. Credner. Zeitschr. der deutscli. geol. GesellscJi., 

vol. xxii, p. 236. 

1 The type of Corhida pvncfjim, Phillips, from Speeton, cannot be found, and I have not seen any 
specimen which could be satisfactorily ideutitied with that species. Phillips, ' Geol. Yorks.' (1829). 
p. 122, pi. ii, fig. 6. 



CORBULA. 213 

Nou 1885. C0BBULAMEH.A sTRiATULA, /. BiJim. Verhaudl. d. uat. Vereiues d. preuss. 

Rheinl., vol. xlii, p. 144. 

— 1887. — — F. Freeh. ZeitscLr. d. deutscli. geol. Gesellsch., 

vol. xxxix, p. 173, pi. xii, figs. 5—8. 

— 1888. — — G. Midler. Jahrl). d. k. preussiscli. geol. Laud., 

fiir 1887, p. 436. 

— - 1889. CoRBULA STRIATULA, 0. Oriepenkerl. Senou. v. KiJuigslutter (Palseont. 

Abliandl., vol. iv), p. 69. 

— 1897. — —A. Frih-ch. Stud, im Gebiete der bohm. Kreide- 

format., vi, Cliloinek. Schicht., p. 64, 
fig. 83. 

— 1901. CoEBULAMELLA STEiATUi.A, F. Stumi. Jalirb. d. k. prenssisch. geol. Land., 

fih- 1900, vol. xxi, p. 88. 

Description. — Shell ovate, usually mucli inflated, produced and pointed 
posteriori)', inequilateral, slightly inequivalve. Anterior and ventral margins 
rounded. Posterior margin short, obliquely truncated. Umbones l)road, strongly 
incurved, with a carina extending to the postero-ventral angle and cutting off 
a flattened postero-dorsal area. Ornamentation consists of numerous concentric 
ribs which extend on to the postero-dorsal area, where they are narrower and more 
distinct. 

Measurements : 

(1) (-') (3) 

Length . 6"7 . 6*0 . 5"5 mm. 

Height . 5-0 . 4-2 . 4-0 „ 

(1) Atherfield Beds, East Shalford ; (2, 3) Crackers, Atherfield. 

Affinities. — This species is distinguished from C. neocomiensi,^, d'Orbignj-,^ by 
the smaller and more pointed posterior end. It differs from G. suhstriatula in being 
less inequivalve and in possessing a distinct carina. WoUemann considers that 
C. Isevis, Maas, is identical with C. striatala. Another form which appears to be 
closely allied is G. neverisensis, de Loriol,- from the Gault of Cosne. 

Remarks. — This species varies considerably in convexity and in relative length 
and height. The shorter, more globose, and more distinctly rostrate forms agree 
with the type. The more elongate and less convex forms are not so numerous, 
and although differing considerably in shape from the globose forms, yet they 
agree with them in other respects and do not appear to be specifically distinct. 

Specimens from the Lower Greensand of Punfield resemble G. striatula, but 
possess stronger concentric ribs — in some cases, as in the example figured (Plate 
XXXIV, fig. 13), the ribs are consideral)ly stronger, but in others the difference 



IS not so great. 



1 'Pal. Fraue. Terr. Crct.,' vol. iii (1846), p. 457, pi. ccclxxxviii, figs. 3 — 5, and ' Prodr. de Pal.,' 
vol. ii (1850), p. 76. 

'- • Gault de Cosne' (1882), p. 43, pi. v, figs. 23—25. 

28 



214 CRETACEOUS LAMELLIBRANCHIA. 

T^ipe. — Internal casts from the Hytlie Beds of Pulborouo-h, in tlie British 
Museum. 

Distribution . — Lower Greensand : Crackers of Atherfield. Recorded by Fitton 
from the Penia-bed, Atherfield Clay, and Beds VI— IX, XIII, XIV near Atherfield. 
Ferruginous Sands of Shanklin. Atherfield Beds of Peasmarsh, East Shalford 
and Sevenoaks. Hythe Beds of Pulborough. Folkestone Beds of Folkestone. 



CoRBULA GADiiTiNA, Pictet and Campiche, 1864. Plate XXXIV, figs. 14 — 16. 

1864. CoEBUL.\. GAULTINA, F. J. Pictet and G. Campiche. Foss. Terr. Cret. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), 
p. 34, pi. c, figs. 3, 4. 

1870. — — F. Stolkzka. Palaeont. Indica, Cret. Fauna S. ludia, 

vol. iii, p. 40. 

Description. — Shell subtriangular, rounded, inflated, slightly inequivalve, a 
little longer than high, moderately inequilateral. Anterior margin rounded. 
Posterior margin subtruncate, oblique. Umbones prominent, rather high, curved 
forward, with an inconspicuous carina cutting off a concave postero-dorsal area. 
Ornamentation consists of small, concentric ribs. 

Measurements : 

(1) (2) (3) (1) 

Length 5*5 . O'O . 4-6 . 4-0 mm. 

Height . 5-0 . 4-5 . 4-0 . 3-6 ., 

(1 — 1) Gaiilt, Folkestone. 

Affinities. — In this species the shell is relatively shorter and more inflated than 
in G. elegantida, d'Orbigny.' 

C. riaidtiua may perhaps be, as was pointed out by Pictet and Campiche, 
identical with G. socialis, d'Orbigny,^ of which no sufficient diagnosis has been 
given. 

Bemarl-s. — Numerous individuals of this species are found close together in 
groups. When the surface of the shell is not perfectly preserved the ribs liecome 
indistinct. 

Tijpe. — From the Gault of Folkestone. 

Distribution. — Lower Gault (Bed 2) of Folkestone. 

1 'Pal. Fran?. Terr. Cret.,' vol. iii (1846), p. 460, pi. ceclxxxviii, fi-s. U— 17. 
3 'Prodr. de Pal.,' vol. ii (1850), p. 136. 



CORBULA. 215 



CoRBUiA TBUNCATA, Sowerbij, 1836. Plate XXXIV, figs. 17 — 22. 

1836. CoRBULA TBUNCATA, /. de 0. Soiverhij. Trans. Geol. Soc, ser. 2, vol. iv, 

pp. 240, 341, pi. xvi, fig. 8. 
1850. — —A. d'Orbigny. Prodr. de Pal, vol. ii, p. 160. 

1854. — — /. Morris. Cat. Brit. Foss., ed. 2, p. 196. 

1868. — — A. Briart and F. L. Cornet. Meule de Braequegnies 

(Mem. cour. et Mem. des Sav. etraugers, vol. xxxiv), 
p. 81, pi. vi, figs. 13 — 15. 
1870. — — F. Stoliczka. Palseont. Indica, Cret. Fauna S. India, 

vol. iii, p. 40. 
(?) 1895. — cf. — E. Tieasen. Zeitschr. d. deutsch. geol. Gesellsch., 

vol. xlvii, p. 485. 

Non 1846. — — A. d'Orbigny. Pal. Fran9. Terr. Cret., vol. iii, p. 461, 

pi. ccclxxxviii, figs. 18 — 20 (? C. 
Goldfitssiana, Matheron). 

Description. — Shell subquadrate or subtriangular, elongate, rounded, moderately 
convex, inequilateral, slightly inequivalve, considerably longer than high. Anterior 
margin well rounded. Ventral margin slightly convex, its posterior part bending 
upwards. Posterior margin obliquely truncated, forming an acute angle with the 
ventral mai'gin and an obtuse angle with the dorsal margin. Umbones broad, 
with a carina extending to the postero-ventral angle and cutting off a flattened or 
concave postero-dorsal area. Ornamentation consists of numerous fine, concentric^ 
ribs which are continued on to the postero-dorsal area. 

Measurements : 

(1) (2) (3) (4) 

Length ... 9 8*5 8 7'5 mm. 

Height . . . 6*5 6 5'75 5 „ 

(1 — 4) Blackdowu. 

Affinities. — This species is less elongate than C. trnncata, d'Orbigny, and is 
also distinguished by its concentric ornamentation. It differs from C. lineata, 
Miiller,^ in the greater obliquity of the posterior margin and in the more numerous 
concentric ribs. 

Tijije. — From Blackdown, in the Bri.stol Museiun. 

Distribution. — Upper Greensand (zone of Schlivubachia rostrata) of Blackdown. 

' Holzapfel, "Die Mollusk. Aachen. Kreide " (' Palseontographica,' vol. xxxv, 1889), p. 146, pi. x, 
figs. 16—19. 



216 CRETACEOUS LAMELLIBRANCHIA. 

CoRBULA ELEGANS, Sowerhy, 1827. Plate XXXIV, figs. 23 — 28. 

1827. CoRBULA ELEGANS, /. ih' C. Soirerhi/. Mill. Coiicli., Vol. vi, p. 130, pi. (llxxii, 

fi^- 1- 
1850. — —A. d'Orhiijny. Prodr. de Pal., vol. ii, p. 160. 

1854 — — J. Morris. Cat. Brit. Foss., ed. 2, p. 195. 

? 1867. — — ?, E. Gic'ranger. Album Pali-out. de la Sarthe, p. 12, 

pi. xvi, fig. 1. 
1870. — — F. Stoliczka. Palaeont. Indica, Cret. Fauiia S. ludia, 

vol. iii, p. 40. 

Non 1846. — —A. d'Orhujny. Pal. Fraiic. Terr. Cret., vol. iii, p. 460, 

pi. ccclxxxviii, figs. 14 — 17 (C. elegantnla, d'Orbigny, 
1850). 

? — 1847. — — • ?, A. d'Archiac. Mem. Soc. geol. de France, ser. 2, 

vol. ii, p. 302. 

Description. — Shell subtrigonal, rounded, very convex, inequivalve, inequi- 
lateral, a little longer than high. 

Right valve with the anterior ]iart sloping rapidly to the margin ; anterior 
margin rounded; ventral margin convex, its posterior part curving upwards. 
Posterior part produced, compressed, separated from the sides by a groove passing 
from the umbo to the postero-ventral angle ; on the dorsal side of the groove is a 
small carina. Posterior margin truncated, forming approximately a right angle 
with the straight postero-dorsal margin. Umbo prominent, sharp, curved con- 
siderably inward and somewhat forward. Ornamentation consists of strong, 
broad, concentric ribs separated by narrow grooves, except on the postero-dorsal 
area, which is nearly smooth. 

Left valve smaller, less convex, and with smaller ribs than the right valve. 
Postero-dorsal area separated from the side of the valve by a groove or sharp 
carina. 

Measurements : 

(1) (2) (3) (4) 

Length ... (3 5'5 5 4"5 nun. 

Height . . . 475 4-5 4 3-G „ 

(1 — 4) Blackdowu. 

Affinities. — This species is distinguished from G. elegantnla, d'Orbigny, l)y its 
broader concentric ribs and rostrate posterior end. It is less globose, less pointed 
posteriorly, and has stronger ribs than C. suhstrintitla , d'Orliigny. 

Type. — From Blackdowu, in the British Museum. 

Distribution. — Upper Greensand (zone of Schlcenbachia rostra fa) of Blackdowu 
and Hal don. Recorded l^y Price from the Upper and Lower Gault of 
Folkestone. 



iPaLxontoovaphical Soctct\>, 1000. 



A M O N O CI R A P H 



CRETACEOUS LAMELLIBIUNCHIA 



ENGLAND. 



HENRY WOODS, M.A. 

UNIVERSITY LECTUKEK IN PAL.E0Z00L08T, CAUBUIDQE. 



VOL. IL PART VI. 

SOLENID^, SAXICAVID.E, PHOLADID.E, TEREDINID.E, ANATINIDiE, 
PHOLADOMYID/E, PLEUROMYID.E, POROMYACIDyE, AND 

CUSPIDARIID^. 

PAaES 217—260; Plates XXXV— XLIV. 



L N D () N : 
PRINTED FOR THE P AL .EONTOG R A P H I C A L SOCIETY. 

1909. 



PKINTEI) BV ADLAUU ANU SON, LONDON AND DORKINO. 



PHARUS. 217 



F^^/«%— SOLENID.E, Lnmarrh. 

Gemis — Pharus, Lench in J. 7?. Grni/, 1847. 

(' Syuops. Brit. Mas.,' e<l 42, 1840, p. 154 ; ' Anu. Mag. Nat. Hist.,' vol. xx, 1847, p. 272 ; 

and ' Proe. Zool. Soc.,' 1847, p. 189.) 

Pharus Waeburtoni (Forhes), 184.3. Plate XXXV, figs. ]— 3. 

1845. SoLECUETUs Warbtjrtoni, E. Foi-hes. Quart. Journ. G-eol. Soc, vol. i, 

p. 237, pi. ii, fig. 1. 
1850. — —A. (VOrbigny. Prodr. de Pal., vol. ii, p. 117. 

1854. — — /. Morris. Cat. Brit. Foss., ed. 2, p. 224. 

1864. — — F. J. Pidet and G. Campiche. Foss. Terr. 

Crct. Ste. Croix (Mati'r. Pal. 
Suisse, ser. 4), p. 30. 
1870. — — F. StoliczJm. Palaeout, ludica, Cret. Fauna S. 

India, vol. iii, p. 99. 

Description. — Shell elongate-oblong, compressed, slightly inequilateral, gaping 
at the ends, the posterior higher than the anterior part. Dorsal margin 
almost straight. Ventral margin slightly flexnous, and shghtly oblique to the 
dorsal margin. Anterior margin rounded. Posterior margin slightly truncate, 
rounded. Umbones small, inconspicuous, sulj-median. Ornamentation consists of 
growth-rings, and on the anterior part of the shell, of numerous, very small, rather 
irregular, radial ribs. 
Measurements : 

(1) (2) (3) (i) 

Length . 67 . 60-5 . 55 . 44- mm. 

Height .17 . IG . 15 . 12 „ 

(1^-4) Crackers, Atherfield. 
Affinities. — This species, as was pointed out by Stoliczka, closely reseml)les in 
foi-ni living examples of the genus Pharus ; but the hinge appears to be miknown, 
for although the species is well represented in collections, and the specimens are 
in an excellent state of preservation, none of them sliows the interior of the shell. 
A single valve resembling P. Warburtoni, but relatively higher, has been described 
by Dr. Kitchin' from the Uitenhage Series. Dr. Harborf- states that his Solecurtus 
lungovatas is similar to our species, but is relatively higher and sliorter. 

1 * Ann. S. African Mus,,' vol. vii (1908). p. 155, fij,'. 1. 

= 'Die Fauna d. Sdiaumburg-Lippe'schen Kreidemuldc ' (1905), p. 71, pi. viii, fig. 6. Au 
imperfect internal cast found in the Upper Greeusand of Devizes shows some i-esemblauce to this 
species. 

29 



218 CKETACEOUS LAMELLIBRANCHIA. 

Tijpe. — From Atlierfiekl, in the Mu«euin of the Geological Society. 
Distribution. — Lower Greensaud (Crackers) of Atlierfiekl. Atherfiekl Beds of 
East Shalford and Sevenoaks. Sandgate Beds of Parham Park. 



Genus — Solecuhti's, //. M. J), df llhn'nrilk', 1824. 

('Diet. Sc'i. luit.,' viil. x-xxii, p. 3-51.) 

Stih-f/enus — Azoii, 11^. E. Latch, 1847. 

(In Gray, ' Ann. Mag. Nat. Hist.,' vol. xx, p. '272 ; and ' Proc. Zool. Soc.,' 1847, p. 189.) 

SoLECDRTUS (AzoK r) PEi,.\Gr, iVOrhii/in/, 1 8")0. Plate XXXV, fig. 4. 

1850. SoLECURTUs Pelagi, a. d'Orhiijnij. Prodr. de Pal., vol. ii, p. 1.58. 

1867. — — E. Gurromjer. Album Pak'ont. de la Sarthe, p. 12, 

pi. XV, fig. 6. 
1870. — — F. StoJiczha. Palseont. Indica, Cret. Fauna S. India, 

vol. iii, p. 99. 

Descrij)tion. — Shell elongate, considerably inequilateral, moderately convex, but 
slightly concave at the middle of the sides. Postero-dorsal area flattened or slightly 
concave, limited by an indistinct carina. Antero-dorsal margin cui-ved ; anterior 
margin rounded; postero-dorsal margin straight, nearly j^arallel to the ventral 
margin; posterior margin curved, slightly oblique. Ornamentation consists of 
small concentric ribs near the umbo, and of growth-rings elsewhere. Length :?0 
mm. ; height 12 mm. 

Ajjiuities. — The identification of the English specimens with tl'Orbigny's species 
is not quite free from doubt, since only two valves, both somewhat imperfect, have 
yet been seen. In the specimen figured by Gueranger the postei'o-dorsal area 
seems relatively higher than in our si)eciiHens ; also the postero-dorsal margin is 
less nearly straight, but this difference may be due to imperfect preservation. 

S. Pelagi seems to be closely allied to S. Guc.ra>if/erl, d'Orbigny,' but the 
carina is less distinct, and the postero-ventral angle appears to be more rounded. 

Until specimens showing the hinge satisfactorily have been found, the generic 
position of this species must be regarded as doubtful. 

Ti/pe. — From the Cenomanian of Le Mans. 

Distribution. — L^pper Greensand (zone of SclihrnlKicJiin ruatrdtn) of Blackdown. 

^ 'Pal. Frany. Terr. Crt't.,' vol. iii (1845), p. 321, pi. cccli, figs. 1, 2. Gut'ranger, 'AUnun 
Pak'ont. de la Sarthe' (1867), p. 12, pi. xv, fig. 4. An inturual cast of a left valve from the Upper 
Gi'eensaud of Warminster resembles S. Guerangeri. 



LEPTOSOLEN. 219 



SoT.ECUKTus? (Azoii?) AcTEOx, iVOrhhjmj, 1850. Plate XXXV, figs. 5, G. 

1850. SoLECURTUs AcTEON, A. d'Orhiijiiy. Prodr. cle Pal., vol. ii, p. 158. 

1867. — — E. Giii'ranyer. Album Pak'out. de la Sarthe, p. 12, 

pi. XV, figs. 1, 2. 
1870. — — F. Stoliczha. Palseont. ludica, Cret. Fauna S. India, 

vol. iii, p. 99. 

Description. — Shell somewhat oblong, moderately inequilateral, moderately 
conve.x, witli flattened sides and flattened postero-dorsal area. Anterior margin 
rounded ; postero-dorsal margin nearly straight, sloping ventrally fi'om the umbo; 
posterior margin slightly convex, somewhat oblique ; ventral margin nearly parallel 
to the dorsal margin and forming a rounded angle with the posterior margin. 
Umbones broad, inconspicuous. Ornamentation consists of strong, regular, con- 
centric ribs, separated by furrows of greater breadth. 

Measurements (approxhaatc) ; 

(1) (2) 

Length . . . 46 . 20 mm. 

Height . . . 24 . 10 „ 

(1) Haldou, (2) Dunscombe. 
Affi)dties. — Only two specimens have been seen ; they resemble closely 
Cxueranger's figures of -S'. Adeon. The hinge is unknown, so that the generic 
position cannot be determined at present. 
Type. — From the Cenomanian of Le Mans. 

Distribution. — Upper Greensand (zone of ScJdd-iiIinrhia rostnita) of Haldon. 
Cenomanian (]\Ieyer's Bed 10) of Dunscombe, South Devon. ^ 

G'ejnf.s'^LEiTOSor.EN, T. A. Conrad, 1867. 

('Amer. Jouru. Couch..' vol. iii, pp. 15, 188 ; F. B. Meek, 'Invert. Cret. and Tert. Foss. 

U. Missouri,' 1876, p. 252.) 

Leptosolen Dupixr.ANUs (d'Orhiijuij), 1845. Plate XXXV, figs. 7, 8. 

18-15. SoLEN DupiNiANUS, A. (V Oihlij)) I/. Pal. Frauc. Terr. Cret., vol. iii, p. 320, 

pi. cccl, figs. 3, 4. 
1850. — — A. d'Orbi(jny. Prodr. de Pal., vol. ii, p. 135. 



1 An internal cast from the Ceuomauiau (Bed 11) of Dunscombe, South Devon, resembles 
Soleciirtiif !i'(ii(a}is, d'Orbigny, l>ut is not sufTuientlv well-preserved for ideutificatiou. S. /cqiialig has 
been referred doubtfully to the genus rharrlln by Stoliczka and by Meek, whilst de Loriol regards it 
as belonging to Siliquaria (= Tagahig). See d'OrV)igny. 'Pal. Fi-au?. Terr. Cret.,' vol. iii (1845), 
p. 321, pi. cccl, figs. 5—7, and 'Prodr. de Pal.,' vol. ii (1850), p. 158; Gueranger, ' Allmm 
Paleout. de la Sarthe ' (1867), p. 12. pi. xv, fig. 3. 



220 CRETACEOUS LAiMELLIBRANCHIA. 

1864. SoLEN DUPiNiANUs, F. J. Ficfii and G. Caiiipiche. Terr. Cret. Ste. Croix 

(Mati'r. Pal. Suisse, ser. 4), p. 29. 

1897. — — R. B. Neivtoii. Proc. Dorset Nat. Hist, aud Antiq. 

Field Club, vol. xviii, p. 93. 

Description. — Shell ulongate, more or le.ss oblong, slightly convex, coinpre.ssed 
near the antero-dorsal margin, considerably inequilateral. Dorsal margin nearly 
straight. Anterior end roimded, not so high as the posterior part of the shell. 
Ventral niai'gin nearly straight and neai'ly pai'allel to the dtirsal margin, curving 
upAvards anteriorly. Posterior margin convex, forming a rounded angle with the 
ventral margin. Umbones small, inconspicuous, situated at less than a third of 
the length of the shell from the anterior margin. 

Ornamentation consists of small concentric ridges; in some cases the ridges 

cut the ])osterior part of the ventral margin obliquely. A strong internal rib 

extends from the umbo veutrally, l)ut does not reach the venti-al mai'giii. 

Measurements : 

W (2) (a) 

Length . . 31 . 29 . 2G mm. 

Height . . 10 . 10 . 9 „ 

(1—3) Gault, Black Veu. 

AQiniticfy. — The occurrence of this species in the Gault of England has been 
recorded by De Ranee and R. B. Newton — by the former from Black Ven, and by 
the latter from Okeford Fitzpaine. Although the example figured by d'Orbigny 
is imperfect, consisting of the posterior part of a left valve only, yet the English 
specimens agree sufficiently closely with d'Orbigny's figure to make it probable 
that they have been correctly identified with fj. Diqnnianus. In most of the 
English examples, however, the posterior margin is more convex and the ])ostero- 
dorsal angle more rounded than in d'Orbigny's figure; but in a few s^jeciniens, 
which have been slightly crushed, these differences are not noticeable. 

The species which resemble L. JJiqnniaiiKS are A/. ro)u-riitrisfriiihi!> (Miiller'), 
L. Petersl (Reuss"), /;. fnnicuhila (Reuss'^), L. ]\liire<tna (d'Orbigny') and /,. liimita 
(Stoliczka"'). 

Ti/pc. — From the Albian of Ervy (Aube). 

JJlstrlhution. — Lower Gault of Black Yen antl Okeford Fitz|)aine. L'lqier Green- 
sand of Devizes. Recorded by Jukes-Browne from the Gault of the Isle of Wight. 

' ' Jalirli. d. k. preussiseh. i,'e(il. Laudesanst. i'iir 1887 ' (1888), p. 4ol, pi. xviii. fii,'. 5. 

' ' Kreidesc-bicht. i. d. Ostalpeu ' (1854), p. 145, pi. xxviii, fiy. lO. Zittel. "Die Bivalv. d. 
Gosaugeb.,' I (1865), p. 5 [109], pi. i, fi;;-. 3. 

^ ' Die Versteiu. derbiibm. Kreidei'i)rinat.,' \t\. '1 (1846), p. 17, pi. xxxvi. fi,L;.s. 13, 16, 17. 

» 'Pal. Fraiu;. Terr. Crut.,' vol. iii (1845), p. 324, pi. eecl, figs. 8—10. Tins species bas beeu 
recorded by Barrois from tbe Upper Greensand of Lulwortb and Devi/es ; I bavi; not seen any 
examples from tbosu localities. 

"•> 'Palseout. Indica, Cret. Fauna S. India' (1870). p. 101, pi. i, tigs. 12, 13. 



PANOPEA. 



221 



Faurih/— iiAXlCAY ID JE, Gnnj. 

Geiuis — Panoi'EA, Mthiard df la <!rtiijc, 18U7. 
(' Auu. Mus. Hist, uat., Paris,' vol. ix, p. lol, pi. xii.j 

Panopea, sp. Text-fig. 27. 

Internal casts of a larg-e, convex riumj^iea occur in the Tealby Limestone of 



.7 




7/ 




■'^' 




Fia. •J.'. — I'iinopea, s\>. IValliy Limestone, North \\'illiu;^haiii, Lincolnsliiiv. Sedgwick Jluseuin, Camln-idiji'. x |. 

Hainton, Claxliy, and North \\'iIliiiL;Iiani, Llncdlnsliire. In foi'in tliey resemble 
some varieties of /'. (jiinjifis, but tlie posterior part of the shell is more elongated. 
One specimen shows a hirge external ligament, and on a small portion of shell 
indications of radial rows of fine granules are seen. The pallial sinus is large and 
rounded. 



222 CRETACEOUS LAMELLIBRANCHIA. 

Pamu'Ka .spilsiukxsis, sp. iiov. Plate XXXVIII, fig. 2a,h. 

Descrijjtion. — Shell elongate-oval, convex, not very ineciuilateral. Posterioi" 
part more compressed and not so high as the median and anterior parts. Anterior 
margin rounded; ventral margin slightly cnrved, not ([uite parallel to the long 
dorsal margin. Umbones broad, incnived, at about six-fifteenths of the entire 
length from the anterior end. Pallial sinus large, deep, and rounded. Surface of 
shell nearly smooth. 

licnuiJ'kti. — Only a few internal casts with small portions of the shell preserved 
have been obtained, but they seem to differ considerably from other species and 
are provisionally referred to the' genus I'aiinpea. 

Distribiifioii. — Spilsby Sandstone (zone of Belemnites lutrralb) of Donnington. 



Paxopea GUKKiTis {Brunyidaii), 1822. Plate XXXV, figs. 9—U; Plate XXXVI, 

figs. 1—8. 

1822. LuTRARiA GVRGniii, A. Briiiniiiiart, in Ciivier. Ossemeus Foss., vol. ii.pt. 2, 

pp. 333, 61.5, pi. ix, fig. 15. 

1823. Mya plicata, J. de C. Sowerhy. Min. Conch., vol. v, p. 20, pi. ccccxix.fig. 3. 
183-5. Panop.ea plicata, Soirerbi/. Ibid., vol. vi, Systeiuat. Index, p. 2-11. 

1841. — — F. A. Rijmev. Die Verstein. d. nord - deutscli. 

Kreidegeb., p. 75, pi. ix, fig. 25. 

1842. Phiiladomya neocomiensis, A. Leymerie. Mcni. Soc. gt'ol. de France, ser. 2, 

vol. V, p. 3, pi. iii, fig. 4. 

— — Prevosti, Beshayesf in Leymeri-;. Ibid., p. 3, pi. ii, fig. 7. 
1845. Panop.ba neocomiensis, A. d'Oiiiiijny. Pal. Fraiic. Terr. Cret., vol. iii, 

ji. 329, pi. cccliii, figs. 3—8. 

— — Pkevosti, d'Orhnjny. Ibid., p. 334, pi. ccclvi, figs. 3, 4. 

— NEOCOMIENSIS, £. jFor6e». Quart. Joui ii. Geol. Soc, vol. i, p. 288. 

— — PLICATA, Forbes. Ibid., p. 238. 

— Mtopsis NEOCOMIENSIS, L. ^(/n««('2. Jltudes crlt. Moll. Foss., M\es, p. 257, 

pi. xxxi, figs. 5 — 10. 

— — UNioiDES, Aijassiz. Ibid., p. 258, pi. xxxi. figs. 11, 12. 

1850. Panop.ea NEOCOMIENSIS, A. d'Orhiijny. Prodi', de Pal., vol. ii, pp. 73, 117. 

— — Prevo.stii, d'Oi-hiijiiy. Ibid., pp. 105, 117. 

1852. — plicata, F. J. Pirti't and W. Koux. Moll. Foss. Grcs verts de 

Geneve, p. 399, pi. xxviii, fig. 2. 

— — Khodani, Fictt'l and Muiix. Ibid., p. 400, pi. xxviii, tig. 3. 

1854. MvAciTES NEOCOMIENSIS, /. Morris. Cat. Brit. Foss., ed. 2, p. 213. 

1855. Panop.«a — F. J. Pictet and E. Renevler. Foss. Terr. Aptieu 

(Mati'r. Pal. Suisse, ser. 1), pp. 56, 175, pi. vi, 
figs. 2, 3. 

— — plicata, Ficfet and Renevier. Ibid., p. .')7, pi. vi. figs. 4, 5. 



PANOPEA. 223 

1855. Panop^a neocomiensis, G. Cofteau. Moll. Foss. de rYoime, p. 51. 

1861. — — P. de Loriol. Auim. Invert. Foss. Mt. Salcve, 

p. 55. 

1864-5. — — F.J.Plctei (vid G.CampicJie. Foss. Terr. Civt. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), 
p. 49, pi. c, figs. 10—12. 

1865. — PLICATA, Pictet and Campiche. Ibid., p. 63. 

1869. — NEOCOMIENSIS, P. de Loriol and V. Gilli'-roii. Urgoii. infer, de 

Lauderou, p. lH, pi. i, fig. 10. 

1870. — — F. StoHczka. Palseont. Indica, Cret. Fauna S. 

India, vol. iii, p. 87. 
1877. — PUNCTATO-PLICATA, 6r. !?"/(//(. Zeitschr. d. deutscli. geol. Gesellscli., 

vol. xxix, p. 241. 
? 1883. — PLICATA, W. Keeping. Foss., etc., Neoc. Upware and BriL-kliill, 

p. 126. 
1884. — NEOCOMIENSIS, O.Weertli. Die Fauna des Neoeom. iniTeutuburg. 

Walde (Palaeont. Abhandl., vol. ii), 
p. 37, pi. viii, fig. 7. 
1886. Pleuromya — H. Trautschold. Ncocom. de Sably (Nouv. Mi'ni. 

Soc. Impi'r. Nat. Moscou, vol. xv), p. 135. 
1892. Panop.s:a — O.Behrendsen. Zeitsehr.d.deutseh.geol.Gesellsch., 

vol. xliv, p. 20. 

1895. — — G. Maas. Ibid., vol. xlvii, p. 256. 

— — — F. Voijel. HoUiiudiscli. Kreide, p. 59. 

1896. — — A.WoUemann. Zeitscbr.d. deutscli.geol.Gesellscli., 

vol. xlviii, p. 849. 

1897. Pleuromya plicata, R. B. Newton. Proe. Dorset Nat. Hist, and Antiq. 

Field Club, vol. xviii, pp. 71, 93, 
pi. ii, figs. 4, 5. 

1898. — NEOCOMIENSIS, E. G. Sheat and V. Madsen. Jur. Neoc. autl 

Gault Boulders in Denmark (Danmarks geol. 

Uudersog., 2 K., Nr. 8j, p. 185, pi. vi.fig. 11. 

1900. Panop^a — A.WoUemann. Die Biv. u. Gastrop. d. deutsch. 

u. bolliiud. Neoconis (Abhandl. d. k. 
preussisch. geol. Laud., N. F., pt. 31), 
p. 124. 

1905. — — E. Harhort. Die Fauna d. Schaumburg-Lippe- 

'schen Kreideniulde (ibid., pt. 
45), p. 74. 

1906. — — A. WoUemann. Jalirb. tl. k. preuss. geol. 

Landesaust. fiir 1906, vol. 
xxvii, p. 278. 
1908. — — A. Stojanoff. Ann. gi'ol. et miu. de la Eussie. 

vol. X, p. 115. 

Non 1827. Lutearia guroitis, S. Nilsson. Petrif. Suecaua, p. 18, pi. v, fig. 9 (Ghjci- 

meris Hohap/eli, Henuig). 
— 1837. — — W. Hisinijer. Lethsea Suecica, p. 67, pi. xx, fig. 1. 



224 CRETACEOUS LAMELLIBRANCHIA. 

Nou 1840. Panop^a gcrgites, A. Golclfiiss. Petref. Germ., vol. ii, p. 274-. pi. iliii, 

fig. 7 (P. G'oldfiisei, d'Orbigny, 
1850). 

— — — PLicATA, Gohlj'iisn. Ibiil., p. 274, pi. olviii, fiyj. 5. 

— 1845. — G0RG1TIS, A. d'Orbigny. Pal. Fraiu;. Terr. Crt't., vol. iii, p. 345, 

pi. ccclxi, fiys. 1, 2. 

— 1846. — — A. E. Ueass. Die Versteiu. der bijluu. Kreideforiiuit., 

pt. 2, p. 17, pi. XXX vi, fig. 3. 

— 1847. — PLICATA, /, Mailer. Petref. der Aachen. Kreidef., pt. 1, p. 28 

{Glycliiieris Gehiitzl, Holzapfel). 

— 1873. — GTJEGiTis, H. B. Geinitz. Das Elbtluilgeb. iu Sachsen (Palaeouto- 

grapbica, vol. xx, pt. 2), p. (58, pi. xix, 
figs. 1, 2. 

— 1876. — — D. Braiiiin. Zeitselir. f. d. gesammt. Naturvviss., vol. 

slvi, p. 362. 

— 1877. ■ — — A. Fritsch. Stud, im Gebiete der bohni. Kreideformat., 

ii, Weissenberg. ii. Maluitz. Scliicliten, 
p. 125, fig. 100. 

— 1898. Glycimeris — G. Miiller. Die Mollusk. d. Uuterseuou v. Braim- 

selnveig u. Ilsede, p. 70, pi. x, fig. 4. 

— 1901. Panop/EA — F. Sturm. Jalirb. d. k. preuss geol. Landesanst. fiir 

1900, vol. xxi, p. 70, pi. X, fit;. 4. 

Description. — Shell more or less oblong, rounded, convex; posterior part 
somewhat compressed, anterior part sloping more or less rapidly to the margin ; 
moderately or considerably inequilateral ; i)Osterior gape large. Anterior margin 
more or less convex, sometimes subtrimcate ; antero-ventral margin rounded; 
ventral margin slightly or moderately convex, nearly parallel to the dorsal margin ; 
posterior margin convex, or subtrnncate and rounded ; postero-dorsal margin 
nearly straight. Umbones incurved, often broad, sometimes narrow and pointed ; 
the dorsal part of the shell in front of the umbones is moderately or considerably 
depressed ; sometimes a more or less distinct carina extends from the umbo 
towards the antero-ventral extremity ; another carina, usually faint, may extend 
from the umbo posteriorly. Pallial sinus large, rounded. 

Ornamentation consists of concentric folds, wliicli may l)c conspicuous or only 
faintly indicated, and of nunicrons radial rows of minute granules. 

Measuremeiifs : 

(3) (4) (5) (.1) 

G9 . 65 . 01 . 5(5 
:]G . 88 . 35 . 29 

(1, 5) Pec»a-bed, Atlierfield. 
(3, 4, 6—9) Crackers, Atlierfield. 

(2) Ferruginous Sands, Sliankliu. 
Affinities. — This species has been referred by most authors to the genus 





(1) 


(2) 


Length 


. 93 . 


, 80 


Height 


. 49 


. 46 



(-) 


(«) 


(9) 


50 . 


, 43 , 


33 mm. 


29 


. 24 


. 19 „ 



PANOPBA. 225 

Panopea, but l:)y some to Plenrouiija.^ There seems now to be sufficient evidence 
to show that it belongs to the former rather than the latter, since the hinge-margins 
of the two valves are alike and there is no overlap of left by the right margin ; 
the hinge possesses the prominent, conical tooth characteristic of Panopm (Plate 
XXXVI, fig. G); and a well-developed, broad, external ligament is present (Plate 
XXXV, figs. 9 i, 1 1 h). The fine radial ornamentation (Plate XXXV, figs. 9 c, 13 //) 
agrees perfectly with that found in Tertiary species of Panojjea.'' I have not seen 
the hinge in any specimen from the Lower Greensand, but it is well preserved in 
a left valve from Blackdown. Pictet and Campiche^ state that casts from the Aptian 
show clearly the presence of the teeth of Panopen. 

Pictet and Renevier thought that P. pUratit (Sowerby) and P. neocomiensis 
(Leymerie) should be united as one species ; Pictet and Campiche, however, in a 
later work regarded them as distinct, and stated that the former differs from the 
latter ])y the possession of strong concentric folds and by the absence of fine radial 
ornamentation. But when iiumerous specimens are examined all stages in the 
strength of the folds can be seen ; and those with well-developed folds show, when 
the surface is well-preserved, the same kind of radial ornamentation that occurs on 
specimens with indistinct folds. The presence of a carina in front of the umbones 
and the somewhat smaller height of the posterior part of the shell have also been 
mentioned as characteristic of P. rtcocomiensix, but these features are now known 
to be inconstant. It appears, therefore, that there is no character by which P. 
pHcala can be separated from P. neocomiensis. 

It is evident from Brongniart's remarks that his specimens of Lntrnriu gurgitis 
came from the Perte-du- Rhone. Pictet and Renevier,^ who had seen the type of 
that species in the collection of M. Deluc, recognised it as a specimen from the' 
Aptian of the Perte-du-Rhone, and state that it is certainly an example of either 
P. neocomiensis or P. plica ta. Since these two forms are now united it follows 
that the earlier name given by Brongniart should be used for this species. Later 
writers liiive unfortunately used the name gm-gHis for a species from the Chalk. 

P. acutisulcatd (Deshayes'') and P. Srhri'xJi'ri (^Yollemann^) appear to be closely 
allied to P. gin-gifis. 

1 For au accouiit of tho characters of this wenus see Terqueni, ' Bull. Soc. geol. cle France,' ser. 3, 
Vol. X (1853), p. 634, and " Observations sur les Etudes critiques des MoUusques Fossiles compreuaut 
la monographie des Myaires de M. Agassiz," ' Mem. Acad. Imp. de Metz,' aimce 1854 — 55 (1855), p. 253. 

- See, for instance, P. intermedin (Sow.) from the London Clay, etc., and P. //orirfrtHot, Heilprin, 
from the Caloosaliatchie Beds of Florida. '^ ' Terr. Cret. Ste. Croix ' (18G5), p. 51. 

' ' Foss. Terr. Aptieu ' (• Mater. Pal. Suisse,' ser. 1, 1855), pp. 56 (footnote), 175. 

5 Leymerie, ' Mcui. Soc. geol. de France,' ser. 2, vol. v (1842), p. 3, pi. iii, fig. 2; d'Orbigny, 
' Pal. Franc. Terr. Cn't.,' vol. iii (1845), p. 336, pi. ccclvii, figs. 1—3 : Pictet and Campiche, 'Terr. 
Crct. Ste. Croix" (' Mater. Pal. Suisse,' ser. 4, 1865), p. 65. 

" ' Die Biv. u. Gastmp. il. (Umtscli. u. holliind. Neocoms ' (' Abhandl. d. k. preussisch. geol. Laud., 
N. F., pt. 31, 1900), p. 126. pi. v, fig. 7. 

30 



22G CRETACEOUS LAMELLIBRAXCHIA. 

./'. heciusfula (Sowerby'), from the Upper Greensand of Blackdowii, closely 
resembles the small forms of the neocomiensis variety of P. gargitis and does not 
appear to be specifically distinct. The type consists of an imperfect right valve ; 
a specimen similar to the type, l)ut with both valves preserved, is in tlie Museum 
of Practical Geology (No. 23,823). 

Remarks. — Previous writers have remarked on the great amount of variation 
shown by this species. At first sight some of the varieties appear to be distinct, 
but, as Wollemaun has pointed out, when a large number of specimens are 
studied, transitions can be traced between the different forms. The varieties do 
not appear to be confined to definite horizons, and nearly all of them are found 
together in the Perna-hed and Crackers of Atherfield. 

Considerable differences are seen in the position of the umbones, so that some 
specimens are much more inequilatei'al than others ; in those in which the anterior 
part is relatively short the anterior slope is rapid. The size and depth of the 
depression in the lunular region show considerable variation ; when large and 
deep the umbones are usually narrower and more pointed than when the depression 
is small and shallow, and in the former case the carina extending from the umbo 
to the antero-ventral margin is usually distinct. The relative length and height 
of the shell, the roimded or truncate character of the anterior margin, tlie 
. curvature of the ventral margin, the height of the posterior end, and the convexity 
of the anterior compared with that of the posterior part of the shell also show 
more or less considerable differences. The concentric folds may be conspicuous, 
but ai"e sometimes indistinct; sometimes they appear to be better marked on 
internal casts than on the shell itself ; in some cases their prominence is due to the 
state of preservation of the shell ; thus Wollemann mentions a specimen in 
which one valve is weathered and shows strong folds, whilst the other valve is 
well preserved and nearly smooth. 

Some forms of this species arc represented l)v a larger niiml)er of individuals 
than others. One common form (Plate XXXVI, figs. 3, 4), agrees more or less 
closely with the type of P. ph'cdfa (Sowerby), and it may perhaps be convenient 
to refer to this as P. giirgitis var. pUrafa. In this the concentric folds are usually 
prominent, the ventral margin is only slightly curved, the posterior part of the 
shell is of nearly the same height as the anterior part, and the lunidar depression 
is distinct and usually lai'ge. 

Another form (Plate XXXV, figs. 9, 13) resembles P. neocomiensis (Leymerie) 
and may be referred to as P. giirgitis var. neocomiensis. The concentric folds are 

1 Mya Ixvinscula, J. de C. Sowerby, 'Trans. Geol. Soc.,' ser. 2 (1836), vol. iv, pp. 241, 340, 
pi. xvi, fijr. 6 ; Morris, ' Cat. Brit. Foss.,' ed. 2 (1854), p. 212. Panopn'a hevuiscula, d'Orbignv, ' Prodr. 
de Pal.,' vol. ii (1850), p. 157; Pictet and Campiche, 'Terr. Cret. Ste. Croix' ('Mater. Pal. Suisse," 
ser. 4, 1865), p. 70. 



PANOPEA. 227 

usually less distinct than iu tlie variety jjlicatK, the luuular depression is smaller 
and shallower, the umbones broader, and the ventral margin usually more distinctly 
curved. The smaller specimens of the var. neocomiensis resemble the example 
figured by d'Orbigny, in which the anterior margin is obliquely truncated, and 
a carina extends from the umbo antero-ventrally. 

In one form (Plate XXXV, fig. 10), which in other respects resembles the 
variety neocomiensis, the anterior half of the shell is relatively more inflated, and 
the posterior part is not so high as the anterior part ; this form may be known 
as P. ijurgilis var. a. In addition to these forms of Z'. gwrgitis numerous other 
modifications occur. 

Specimens from the Speeton Clay have been recorded by previous writers as 
P. neocomiensis; the examples seen are few in number and not well preserved, 
but resemble closely the smaller form of P. gun/if is var. neocomiensis (Plate XXXV, 
fig. 13). In one case the fine, radial ornamentation is shown. 

Specimens from Blackdown (Plate XXXVI, figs. 6, 7) resemble the variety 
2)lic<ifii from tlie Lower Greensand, but are somewhat less convex ; these probablv 
constitute only a local variety, since examples from the Upper Greensand of Dorset 
agree in convexity and in other characters with typical forms of the var. plicafu 
from the Lower Greensand. The examples from Blackdown, although few in 
number, show considerable variation; one specimen (Plate XXXVI, fig. 8), is 
nuich shorter than usual, and resembles d'Orbigny's^ figure of P. pUcata, but 
is less convex. 

Crushed internal casts of Panopea have been found in the Chalk ]\Iarl of 
Folkestone ; they resemble P. gnrgitis var. jilicatu, but their imperfect preservation 
renders determination difficult. 

Ti/pes. — The type of 1'. gnrgitis came from the Aptian of the Perte-dn-lihnne ; 
that of P. neocomiensis from the Xeocomian of Aubc. The type of /'. pUcnfn 
was obtained from the Lower (Greensand of Sandgate, but cannot now be found. 
The type of /'. Igeviuscula, from the Upper Greensand of Blackdown, is in the 
Bristol iluseum. 

Distriliiition. — Lower Greensand : Perna-hed, Crackers and Beds iv, vi, vii, x, 
xiii, and xiv of Atherfield. P«-/(''-bed of Sandown. Ferruginous Sands of Slianklin. 
Atlierfield Beds of East Shalford and Scvcnoaks. Hythe Beds of Hythe and 
Court-at-Street. Sandgate Beds of Pai liani Park. ^[(lmnliUlJfns Bed of Folke- 
stone. Recorded 1)V T()})ley from the Atherfield Chiy of Haslemere, Peasmarsh, 
Redhill, aiul Hythe; from tlie Hythe Beds of Pulborough; from the Sandgate 
Beds of Folkestone and Sandgate ; and from the Folkestone Beds of Folkestone. 
? Lower Greensand of L^pware. PSpceton Clay of Speeton. Gault of Black Yvu 
and Folkestone. Upper Greensand of Blackdown and Black Ven. 

1 ' Pal. Franc. Terr. Crt't.,' vol. iii (1845), p. 337, i>\. ccclvii, figs. 4, 5. 



228 CRETACEOUS LAilELLIBRAXCHIA. 

Panopea mandibcla iSowerhi/), 1813. Plate XXXVII, figs. 1—5. 

1813. Mta mandibtjla, /. Sowerby. Min. Conch., vol. i, p. 93, pi. xliii. 
? 1840. Panop.sa BArMONTii, A. Goldfuss. Petref. Germ., vol. ii, p. 274, pi. clviii, 

fig. 4. 
? 1841. — Jvaj^Eui, F. A. Rnmer. Die Verstein. d. nord-deutseh. Kreidegeb., 

p. 75. pi. X, fig. 4. 
1845. — MANDiBULA, A. d'Oihlyiiy. Pal. Fran9. Terr. Crt't., vol. iii.p. 344, 

pi. cccls, figs. 3, 4. 
1850. — — H. B. Geinifz. Das Quadersandst. oder Kreidegeb. 

iu Deutschland, p. 146. 
1854. Mtacites mandibula, /. Morris. Cat. Brit. Foss., ed. 2, p. 213. 
1865. Panopea — F. J. Piclef and G. Campiche. Terr. Crt't. Ste. Croix 

(Matt'r. Pal. Suisse, ser. 4), p. 70. 
1870. — — J^. Stoliczl-a. Palaeout. ludica, Cret. Fauua S. ludia, 

vol. iii, p. 87. 
1873. — — H.B. GeiiiUz. Das Elbthalgeb. iu Sachseu (Pal- 

aeontographica, vol. xx, pt. 2), p. 
70, pi. xviii, figs. 20, 21. 
? 1883. — — A. Fritscli. Stud, im Gebiete der bohm. Kreide- 

forinat., iii, Iserschielit., p. 108. 
? 1897. — — Friisch. Ibid., vi, Chlomek. Sc-hiolit., p. 60. 

1900. Pi,EUBOMT.\ — A. J. JiiJces-Broicne. Cret. Eocks of Britain, vol. i, 

p. 470. 

Description. — Shell oblong or rliomboidal in outline, very inequilateral, 
convex, anterior part sloping rapidlj^to the anterior margin, with a wide posterior 
gape. Anterior margin somewhat convex ; antero-ventral extremity rounded ; 
ventral margin straight or slightly curved and neai'ly parallel to the dorsal 
margin; postero-A'entral extremity rounded ; posterior margin truncated, nearly 
straight, either perpendicular or slightly oblique to the nearly straight postero- 
■dorsal margin. Unibones prominent, narrow, pointed, considerably incurved, 
with a In'oad, .shallow furrow extending from their posterior side to the postero- 
ventral i)art of the valves. In front of the umbones the shell is considerably 
depressed. 

Ornamentation consists of strong, rounded, concentric folds, which become 
less distinct in and posterior to the dorso-ventral furrow; and of radial rows of 
minute granules. 

Measurements ; 





(1) 


(2) 


(3) 


W 


(5) 


(6) 


Length 


72 , 


. 70 , 


. 53 


. 53 , 


, 49 , 


36 mm 


Height 


57 . 


. 46 . 


41 


. 38 . 


. 35 . 


33 „ 


Thickness . 


41 


. 39 


— 


. 28 


. 20 , 


. 27 „ 



(1, 4 — 6) Upper Greensand, Veutuor. 
(2, 3) Upper Greensaud, Devizes. 



PANOPBA. 229 

Affinities. — Tlie more elongate forms of this species resemble some specimens 
of /'. (in)-(jitis var. pUcata, but are more inetiuilatcral, more convex, usually 
relatively longer, with narrower and more pointed unibones, and with a distinct 
furrow extending from the undjo to the postero-ventral margin. 

Uemarks. — Many of the specimens are more or less crushed, and nearly all are 
internal casts, but the shell is preserved in some specimens from the (lault, and 
shows radial rows of fine granules. The hinge is not seen in any instance. 
P. mandilnda is common in the Upper Greensand of Ventnor and Devizes, and is 
less abundant at other horizons. The principal variation seen is in the relative 
length and heio-ht of the shell. 

Type. — From the Upper Greensand of Devizes, in the British Museum. 

Distribution. — Lower Greensand of Atherfield. Atherfield Beds of Seveuoaks. 
Sandgate Beds of Nuffield. Folkestone Beds of Folkestone. Upper Greensand 
(zone of SrJihvnhachia rostrata) of Devizes and Yentnor. Gault and Upper 
Greensand of Black Ven. Chalk Marl of Folkestone. 



Panopea ovalis, Soicerhij, 18:36. Plate XXXVII, fig. Q>a,h. 

1836. Panopea ovalis, J. cle C. Sowerby. Traus. Geol. Soc, ser. 2, vol. iv, pp. 

241, 340, pi. xvi, fig. 5. 
1850. — — A. iVOrhiijny. Prodr. cle Pal, vol. ii, p. 157. 

1854. Myacites — /. Morris. Cat. Brit. Foss., ed. 2, p. 214. 

Description. — Shell oval, convex, moderately inequilateral. Antero-dorsal 
margin slightly convex ; anterior margin rounded, passing gradually into the 
slightly convex ventral margin. Unibones broad, incurved. The parts of the 
shell in the front of and Ijehind the umbones are considerably dejjressed. The 
surface is ornamented with growth-rings. 

Remarls. — The only specimen seen is the t\'pe, in which the posterior part of 
the shell is not preserved. 

Tijpe.- — 111 the British ]\Iuseuiii. 

Distribution. — Upjier (ireensand (zone of Schluinbackia ro.ftratu) of Blackdown. 



P.\xoPE.\ Meyeri, sp. nov. Plate XXXVIII, fig. la,b. 

Desiuiptiun. — Shell oval, moderately convex, witli flattened sides, slightly 
inequilateral, with a wide posterior gape. Antero-dorsal margin convex. Anterior 



230 CRETACEOUS LAMELLIBRANCHIA. 

margin rounded. Ventral margin straight or slightly convex. Posterior margin 
truncated, sliglitl}- convex. Postero-dorsal margin slightly concave, nearly parallel 
to the ventral margin. Umbones broad, curved inwards and backwards. The 
part of the shell in front of the umbones is slightly depressed; the part behind the 
umbones is more deeply depressed. Surface with well-marked growth-rings. 
Length 87 mm. ; height 59 mm. 

Aj)i)iifies. — In this species the sides of the shell are more flattened, the autero- 
dorsal margin is more convex, and the part of the shell in front of the umbones is 
less depressed than in P. ocdlis. The hinge has not been seen, but the form of the 
shell agrees closely with that of ty})ical species of Panopea. 




Fig. 28. — Panopea, sp. Lower Greeiisand (' .-^capniti's J.rtls), Whale Chine, Atherfield. Sed-jwick 
Museum. Internal cast of right valve. Natural size. 

Jt'riitarkt^. — In addition to the specimen figured, which was collected by 
C. J. A. Meyer, an internal cast and the posterior part of a left valve only have 
been seen. 

Distribution. — Upper Greensand (zone of ScliUviilntchid rarinna) of Blackdown. 



P.\xnpj;,\, sp. Text-fig. 28. 

Internal casts resembling /'. ^Li'ijcri, but with the po.■^terior border obliquely 
truncated, occur in the Lower Greensand (" Scaphites " Beds) of "Whale Chine, 
Atherfield. 



MARTESIA. 231 

ira„ji/^_PHOLADID.E, Leach. 

Genus — Martesia, Leach in H. M. D. rie Blainville, 1825. 
(' Manuel de Malacol.,' p. 632.) 

Maetesia coNSTEiCTA (rJuIUps), 1829. Plate XXXVIII, figs. 3—10. 

1829. Pholas constricta, /. PJiilhyi. Geol. Torks.,p. 169 (p. 256, ed. 3), pi. ii, 

%. 17. 
1850. — —A. d'Orbigny. Prodr. de Pal., vol. ii, p. 117. 

1854. — — J.Morris. Cat. Brit. Foss., ed. 2, p. 221. 

1864. — — F.J. Field and G. Campiclie. Foss. Terr. Crit. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), 
p. 26. 
1870. — — F. Stoliczka. Palisout. ludica, Cret. Fauua S. ludia, 

p. 23 (? Martesia). 
1900. Pholadidea constricta, A. J. Jukes-Browne. Cret. Eocks of Britain, 

vol. i, p. 470. 

Description. — Shell small, more or less elongate; anterior part short, convex, 
rounded ; posterior part wedge-shaped. Umbones prominent, close together, 
curved inwards and forwards. Ventral margin nearly straight. Posterior margin 
sub-truncate, more or less rounded, somewhat oblique. Postero-dorsal margin 
sloping ventralh'. Two narrow furrows, with corresponding internal ribs, extend 
from the umbo to the ventral margin; the anterior furrow is rather broader and 
less oblique than the posterior, i)ut is sometimes short or absent. An internal » 
ridge, near the postero-dorsal margin, extends from the umbo to near the posterior 
adductor. Anterior callus shield-shaped. Ventral margin of valves diverging 
posteriorly, joined by a hypojdax. Metaplax elongated, divided. 

Ornamentation : on the larger part of the shell distinct, regular, concentric 
ribs with minute transverse sei-rations. In front of the anterior furrow the ribs 
become smaller and closer together; they ])end dorsally and unite at an angle 
with similar ribs on the dorsal })art of the anterior end of the valve. On the 
postero-dorsal part of the shell the ribs are less regular and less distinct. 

Measurements : 

(2) (3) (4) (.^>) 

17 . k; . 18 . 15 

9 . 9 . 10 . 9 

9.9. 10-5. 9 

(1 — 3) Speeton, (4 — 7) Folkestone. 

Affinities. — This species is less elongate than M. subcijlindrica (d'Orbigny).' 
1 ' Pal. Franc. Terr. Crot.,' vol. iii (1845), p. 306, pi. cccxlix, figs. 5—8. 





(1) 


Length 


18 


Height . 


9 


Thickness 


9 



(6) 


(7) 


14 . 


10 mm 


7 


C-5 „ 


7.5 . 


6-5 „ 



232 CRETACEOUS T,A:yrETJJBRANCHIA. 

Tlie height of tlie anterior part of the sliell is less and the length of the ventral 
margin greater relatively than in M. Sandse-CnirU (Pictet and Campiche).' 

Remarks. — This species varies somewliat in relative length and breadth, and 
in the extent of the develo^Jment of the anterior furrow. Many of the specimens 
are found in burrows in Avood. The protoplax is not preserved in any example seen. 

T//pe. — The type came from Speeton, but cannot now be found. 

DistrihuHon. — Speeton Clay of Speeton. Lower and Upper Gault of Folkestone. 
Probably also in the Upper Greensand of Blackdown. Specimens wliifh belong to 
either this or a closely allied species occur in the Spilsby Sandstone of Benniworth 
Haven. Borings in wood found in the Tealby Limestone of Claxb}- may lie due 
to this species but the valves are concealed. 

Martesia ruiscA (Soirerhi/), 1828. Plate XXXVIII, fig. 11. 

]828. Pholas priscus, /. c!e C. Sowerhy. Miu. Couch., vol. vi, p. 157, ]il. dlxxxi. 

1845. Pholas ? priscus, E. Forbes. Quart. Jourii. Geol. Soc, vol. i, p. "237. 

1850. Pholas prisca, A. d'Orbigny. Prodr. de Pal., vol. ii, p. 72. 

1854. — — J.Morris. Cat. Brit. Foss., ed. 2, p. 221. 

1864. - — F. /. Pidet and G. Campiche. Foss. Terr. Crct. Ste. Croix 

(Matt'r. Pal. Suisse, ser. 4), p. 26. 
1870. — — • (Martbsia), F. Stoliczha. Palaeout. ludica, Cret. Fauna 

S. ludia, vol. iii, p. 22. 
1875. Pholadidea prisca, B. Etheridge iii W. Topley. Geol. Weald, p. 419. 

This species appears to be closely related to ill. constricfa, but no satisfactory 

description can be given until better specimens have been obtained. The type, in 

which the shell was well preserved, cannot now be traced ; in other examples the 

shell is concealed by a coating of hard matrix, and in the few cases in which it has 

been possible to remove the matrix only internal casts of the valves have been 

exposed. The type came from the Lower Greensand (? Sandgate Beds) near 

Sandgate. Other specimens have been obtained from the Hythe Beds of Hythe 

and Maidstone." 

1 'Foss. Terr. Cret. Ste. Croix' (1864), p. 24, pi. c, tig. 1. This species has been recorded by 
Price from the Gault of Folkestone ; I have not seen any examples of it. 

- Fistulana pijriformis, Mautell, is perhaps a Martesia, but no specimens showing the valves have 
been seen. No figure or specific description was given by Mautell. The "type" came from 
■VVillingdon near Eastbourne, apparently from the top of the Lower Greensand. Mantell, ' Foss. S. 
Downs' (1822), p. 76- Gastrochiena pyri/ormis, Morris, 'Cat. Brit. Foss.,' ed. 2 (1854), p. 203; 
Pictet and Campiche, ' Foss. Terr. Crct. Ste. Croix (Mater. Pal. Suisse,' ser. 4, 1864), p. 18 ; Stoliczka, 
'Palseont. ludica, Cret. Fauna S. India,' vol. iii (1870), p. 29. 

Gastrochwna dilatafa, Deshayes, has been recorded by Forbes and other writers from the Lower 
Greeusand ; I have not seen an_y specimens in which the valves are exposed. Deshayes, in Leymerie, 
' Mem. Soc. geol. de France,' vol. v (1842), p. 2, pi. iii, fig. 1 ; Forbes, ' Quart. Jouru. Geol. Soc.,' vol. i 
(1845), p. 237 ; Pictet and Campiche, ' Foss. Terr. Cret. Ste. Croix ' (1864) , p. 1 1 , pi. xcix. figs. 4. 5. 



TURNUS. 233 



Martesia? kotuxda {Soirn-hi/), 18-50. Plate XXXVIII, figs. 12 (t—c, 18. 

1850. Teredo eotundtjs, J. de C. Sowei-hy iu F. Dixon. Geol. Sussex, p. 340 (p. 

382, ed. 2), pi. xxviii, figs. 27, 28. 
1854. — — /. Morris. Cat. Brit. Foss., ed. 2, p. 227. 

1897. Martesia ? rotunda, H. Wnixh. Quart. Jouru. Geol. Soc, vol. liii, 

p. 393, pi. xxviii, figs. 15 — 18. 

Description. — Shell small, ovoid, inflated, with rounded outline. Anterior gape 
large, apparently closed by callus. Umbones sub-median, curved inwards and 
forwards. A strong groove and a corresponding internal rib pass from the umbo 
to the ventral margin. Near the dorsal margin a strong, narrow internal rib passes 
backward from the umbo but does not reach the posterior margin. Ornamentation 
posterior to the groove consists of concentric ribs and of two radial ribs imme- 
diately behind the gi'oove; anterior to the groove are a few regular radial ribs, and 
concentric ribs parallel to the margin of the anterior gape. Length, 7 mm. ; 
height, 5'5 mm. ; thickness, 5 mm. 

Bemarlis. — I have seen only three casts of the interior and two of part of the 
exterior of this species, so that at jjresent it is difficult to determine satisfactorily 
its generic position. 

Type. — The type came from the Chalk of Kent, l)ut cannot noAV l)e found. 

Distribiitiuu. — Chalk Rock of Cnckhamsley (Berkshire), and of AVhyteleafc 
(Surrey). 



Genus— TuR^vn, W. M. GahJ,, ISGl. 
(' Geol. Surv. California,' Pala;outology, vol. i, p. 145.) 

TuRNUs Dallasi {Wall-cr), 1866. Plate XXXVIII, figs. 14 a, h, 15. 

18(3(5. Pholas Dallasi, /. F. Walker. Ann. Mag. Nat. Hist., ser. 3, vol. xviii, 

p. 38(5, pi. xiii, figs. 3, 4. 

De.^crij)ti()n. — Shell ovate, short, inflated in front, wedge-like behind. Margin 
of the anterior gape oblirjue, gently curved. Posterior margin rounded. Umbones 
prominent, curved inwards and forwards. A narrow furrow, and a corresponding 
internal rib, extend from the umbo to the ventral margin in a somewhat oblique 

dirt'ctiiin, and the furrow is crossed by small ril).s. A liruad and strong internal ril> 

31 



284 CRETACEOUS LAMELLIBRAXCHIA. 

passes from the umbo to near the postero-ventral margin. The shell is ornamentetl 
with small concentric ribs, which bend dorsally in front of the furrow and become 
parallel to the anterior margin. 

Measurements : 

(1) (2) 

Length . . . 15 . S mm. 

Height . . . 11 . 0-5 ., 

Thickness . . . — . (rb ,, 

Affinities. — The very slight curvature of the anterior margin and nf the anterior 
ribs distinguishes this species from the one described below. 

Remarlcs. — T. DaUasi occurs commonly boring in wood. 

Ti/2w. — From Potton ; in the Sedgwick Museum. 

Dintrihufion. — Lower Greensand of Potton. 



TuRNUS, sp. Plate XXXVIII, figs. KJ, 17. 

Descrijdiun. — Shell oval, inflated, posterior end wedge-like. Ventral margin 
curved ; posterior mai'gin rounded. Antero-ventral excavation angular. Umbones 
prominent, anterior, incurved, close together. An external furrow and a correspond- 
ing internal rib extend from the umbo to the ventral margin. A strong internal 
rib passes from the i;mbo to near the postero-ventral edge. 

Posterior to the dorso-ventral groove the shell is ornamented with narrow, 
regular concentric ribs ; for a short distance in front of the groove the ribs bend 
sharply upwards, and soon become smaller and close together ; on the dorsal part 
of the anterior end the I'ibs I)end forwards. 

Measurements ; 

(1) (2) 

Length . . . 14 . 13 mm. 

Height . . . 11 . 9-5„ 

Thickness . . . 12 . 10 „ 

(1—2) Gault, Folkestone. 

Affinities. — This species resembles T. argoiinensis (Buvignier),^ but exact 
comparison is difficult since only a small internal cast is figured by Buvignier. 
The English form appears to differ from T. argonneasis in the larger size and 
more angular character of the anterior gape, and in the smaller and closer ribs, 
especially on the anterior part of the shell. 

Disfributioii. — Lower Gault of Folkestone. 

1 ' Statist, ycul. iiiiu. ot jiak-out. de la Meuse,' Atlas (1852), p. 6, pi. vi, figs. 33—39. 



TURNU8. 2:35 



TuKNOS, sp. Plate XXXVIII, fig-. 18. 

A specimen from the Upper Greensancl of Blackdown resembles the species 
from the Gaiilt, described above, but the concentric ribs are finer and more 
numerous, antl the dorso-ventral furrow is narrower. The exterior of a left valve 
only is preserved and is associated with large aud rather irregular tubes. 



TuRNUS ? AMPHiSB.Ex\A (Guldfuss), 1831. Plate XXXVIII, figs. 19, 20. 

1822. Teredo, G. MaiiteU. Foss. S. Downs, p. 2u7, pi. .wiii, fiy. 2-3. 
1831. Sebpula amphisb^ena, A. GoJdfuss. Petref. Gremi., vol. i, p. 239, pi. Ixx, 

%'. 16. 
r 1839. Ceeambtcites, sp., H. B. GtinUz. Char. d. ScLiclit. u. Petref. des siichs. 

Kreidegeb., pt. 1, p. 13, pis. iii — vi. 

1840. Teredo amphisb^na, /. de C. Sowerhy. Miu. Couch., vol. vii, p. 17, pi. 

dcxviii, figs. 1 — 5 {Teredo articu- 
Ictta ou the plate). 

1841. Serpula amphisb.ena, F. A. RiViner. Die Verstein. d. uord-dtnitsch. 

Kreidegeb., p. 100. 

1842. — — H. B. Geiiiitz. Char. d. Schicht. u. Petref. des 

siichs. -bohmiscli. Kreidegeb., pt. 3, 
p. 6.5. 

1843. Fistulana amphisb.ena, if. jB. ti'ci'/nVx. Die Versteiu. vou Kiesliugswalda, 

p. 11, pi. iv, figs. 11 — 14. 

1845. SERPrLA XM.vaisBj&j^\, A.E.Reuss. DieVersteiu.derbohni.Kreideformat., 

pt. 1, p. 19, pi. v, figs. 29—32. 

1846. Gastroch.5:na ? (Teredo r) amphisb^na, H. B. Geiiiitz. Gruudr. d. Ver- 

stein., p. 396. 
':* 1850. Fistulana amphisbjjna, P. de EycMolt. Melanges Pak'ont. i (Mem. eour. 

et Mem. des sav. eti-aug., vol. 
xxiv),p. 117, pi. V, figs. 19—22. 

1850. Teredo amphisbcena, /. de C. Sowerhy, in F. Dixon. Geol. Sussex, p. 354 

(p. 385, ed. 2), pi. xxviii, fig. 35. 

1851. Gastroch^ina amphisb^.na, J. Midler. Petref. der Aaeheu. Kreidef., pt. 2, 

p. 63. 
?1852. — — ?, Ji'.A'we/-. Denksehr. d.k. Akad. d. Wisseusch. 

Wien, Math.-nat. CI., vol. iii, 
p. 310, pi. xvi, fig. 18. 
1854. Teredo amphisb.«na, J. Morris. Cat. Brit. Foss , ed. 2, p. 227. 

1863. Gastroch^na amphisbjena, li. Drescher. Zeitsehr. d. deutsch. geol. 

Gesellsch., vol. xv, p. 341. 

1864. — F. J. Pictel and G. Campiche. Foss. Terr. Cret. 

Ste. Croix (Mater. Pal. Suisse, 
ser. 4), p. 19. 



230 CRETACEOUS LAMELLIBRANCHIA. 

1870. Teredo amphisb^sina, J''. RiJmer. Geol. v. Oberschles., jip. ;517, 'S-iO, pi. 

xxxiv, figs. 14, 15. 

— Gastroch^ena AMPHiSBiENA, F. Sfoliczka. PalsDoiit. ludica, Cret. Fauna 

S. India, pp. 14, 29. 
1873. — — I[. n. Gehilfz. Das Ell)thal<,'eb. in Sacliscn 

(Palfeontograpliica, vol. xx, 
pt. 1), p. 235, pi. lii, figs. 
8—12. 

1876. — — D. Braurnt. Zeitsclir. f. d. gesamiut. Natur- 

iviss., vol. xlvi, p. 358. 

1877. — — ■ A. Frilsch. Stud, iiu Gebiete der biilmi. 

Kreideformat. ii, AVeisseuberg. u. Malnitz. 
Sehiclit., p. 122, fig. 93. 

1888. — — G. Miilhr. Jalirb. d. k. preussisch. geol. 

Landesaust. f iir 1887, p. 436. 

1889. — - — A. FritsrJi. Stud, ini Gebiete der bijlnn. 

Kreideformat. iv, Teplitz. 
Scliicht., p. 79, fig. G7. 

— — — 0. Griepenkerl. Senou. v. Konigslutter (Pal- 

ffiout. Abhandl., vol. iv), 
p. 69, (? pi. vii, fig. 1). 
? 1889. ? — — E. Hohapfel Die Mollusk. Aachen. Kreide 

(Palseoutographiea, vol. xxxv), p. 143. 
? 1893. — — Fritsch. Op. cit. v. Priesen. Scliicht., p. 9Q, 

fig. 113. 
?1895. ? — — F. Vogel. Hollundisch. Kreide, p. 49, pi. iii, 

fig. 13. 

1897. — — a. Leonhard. Kreideformat. in Oberschles. 

(Palaeontograpliica, xliv), p. 
53, fig. 8. 

1898. TuRNUs AMPHiSB^NA, 6'. !/''//(;/•. Mollusk. d. Uuterseuon V. P>rauuscliweig 

u. Ilsede (Abhaudl. d. k. preuss. geol. 
Laudesanst., N. P., Heft 25), p. 79, 
pi. X, fig. 12. 
1902. — — A. WoUemann. Fauna der Li'ineburg. Kreide (Ab- 

haudl. d. k. preuss. geol. Landes- 
anst. N. F.. Heft 37), p. 81. 

Description. — Tubes long, conical, tajjering gradually, sonietiraes nearly straight, 
but usually beudiug or curviiig ii'vegularly, circular in scrtioii, but often com- 
pressed, and then showing a median longitudinal furrow on one side. Diameter 
sometimes reaches 15 mm. and the length 210 mm. Surface with narrow^ transverse 
ridges at more or less regular intervals giving a segmented appearance ; sometimes 
also with smaller growth-rings between the ridges. 

Remarks. — This species ranges almost throughout the Chalk and is widely 
distributed. It has been referred l)y various authors to five different genera, but 



TEREDO. 237 

its systematic position must still be regarded as uncertain, tor altliougli the tubes 
ai'e common the valves Lave not been found in association Avitli them. Fritscli 
(1893) and MiiUer (1898) liave Found the valves of 'I'lrnnis in the same deposit as 
the tubes, and think it probable that the former belong to the same species as the 
latter. Some authors have referred these tubes to the genus (lastrorlin'i/u, l)ut 
Stoliczka points out that the}^ resemljle more nearly the tubes of Teredo. 

Tijpea. — From the Senonian of Maestricht and Bochum. The specimens 
figured by Sowerby (except fig. 2, which is in the British Museum), by Mantel), and 
by Dixon cannot l^e found. 

Disfriliittioii. — C'hloritic Marl of Eastbourne. (Aunbridge Greensaud. Chalk 
IMarl of Chard and Ventnor. Zone of Holaster suhglobosus of Holborongh near 
Eochester, Totternhoe, Cherry Hinton, and Burwell. Zone of Bliijnclionella Cuvieri 
of the Devon coast, Winchester, the Isle of AVight, and Lewes. Zone of Terehra- 
tidiiKi of Winchester, the Isle of AVight, Croydon, and Devon. Zone of Holaster 
phinus of the Dorset coast, the Isle of Wight, Dover, and Lnton. Zone of Micraster 
cor-teshuVuutr'uim of Mitcheldevei-, Dover, the Sussex coast, and Coulsdon (Surrey). 
Zone of M. cor-nnguinuin of the Sussex coast, St. Margaret's, Thanet, and Graves- 
end. Zone of Marsiijntes tcstiidinarius of Highfield, near Salisburj-, the Sussex 
coast, and Thanet. Zone of Actiuncnmax qitiidriifns of the Sussex coast. 



i^tr/H////— TEREDINID.E, Scacchi 

Genus — Tkreuo, Liiuia'its, 1758. 
(' Syst. Nat.,' ed. 10, p. 651 ; ed. 12, 1767, p. 1267.) 

Tehedo GAUi/nxA, sp. nov. Plate XXXVIII, fig. 21. 

Prscri/ilioii — Shell convex, inequilateral. Anterior gape large, angular. 
Postero-veutral gape small. Postero-dorsal margin produced upwards and out- 
wards. L'mbones large, incurved. A shallow furrow extends from the umbo to 
the ventral margin. Posterior to the furrow the shell is ornamented with ribs and 
narrow furi-ows, which soon bend iloi'sally, and disappear or become indistinct on 
the postero-doi-sal part; in front of the furrow tiie ribs are much smaller, and 
are pai'alld to the margin of tlie anterioi' ga[ie; at first they are directed dorsally, 
but soon bentl forwards. Length, 9 mm. ; l)readth, 8"-j mm. 

Affinities. — In 1\ rarennensis, Buvignier,^ the anterior ribs are coarser and the 
posterior end of the shell is more produced than in this species. 

Distribution. — Gault of Folkestone. 

1 ' Statist. i,'('ol. mill, ot paKVmt. de hi Meiise," Atlas (1852), p. 6, pi. vi, figs. 40—48. 



238 CRETACEOUS LAMELLIBRANCHIA. 



Genus — Pi.ECTOJiYA, P. de Lnriul, 1868. 
(De Loriol and Cotteau, ' Mou. Pali'oiit. GtoI. Portlandii-n Jo I'Yonne,' p. 89.) 

Plectomya Axrir.icA, sp. iiov. Plate XXXIX, fig. In, J,. 

Description. — Sliell elongate-oval, slightly ineciuilateral, compressed; anterior 
and posterior ends rounded j ventral margin slightly convex. Umboues broad, 
A\ ith a sliglit posterior cm*vature. 

The part of the shell in front of a line drawn fi'om the umlio to the opposite 
ventral margin is ornamented Avith strong concentric ribs separated by broad 
furrows ; these ribs become nearly or quite obsolete on the posterior middle part 
of the shell (except near the umbo), but re-appear on the postero-dorsal part. 
The entire surface of the shell is ornamented with numerous radial rows of 
granules. Length 49 nun ; height 27 mm. 

Affinities. — This species is similar in general character to rjertointja Agassizi 
(d'Orbigny'), but the shell is less elongate, the ribs on the anterior part of the 
shell cut the margin and the growth-lines obliquely, and on the jjosterior median 
part the ribs are almost obsolete. It also shows some resemblance to 1'. EhoJiini 
(Pictet and Ronx'-). 

liemarl-s. — Of this species I have seen only two examples, neither of which 
shows the interior, so that I am unaljle to express an opinion as to afUnities of the 
genus I'lecloiiujii. 

]>isfribntii)ii. — Lower Greensand (Crackers) of Atherfield." 



Genus — Anatixa, Lninarcl-, ISdU. 
(' Philosoph. Zool," vi)l. i, p. 31SI ; ' Hist. iiat. Auiiii. saiis Vert.,' vol. v, 1818, p. 462.) 

Suh-(jenus — Ceucumya, L. Aijassb., 1S42. 
(' Etudes crit. Moll. Foss.," Myes, p. 143.) 

1 'Pal. Franc. Terr. Cn't.,' vol. iii (1845), p. 371, pi. ci-cl.xix, figs. 1, 2; Pictet and Caiupiche, 
'Foss. Terr. Crct. Ste. Croix' ('Mater. Pal. Suisse,' ser. 4, 1865), p. 99, pi. cvii, fig. 1. 

- ' Moll. Foss. Gres verts de Geneve' (1852), p. 410, pi. xxix, fig. 4. 

* An imperfect specimen from the Lower Greensand of Atherfield is probably an e.vample of 
Plectomya maruUensis (d'Orbigny), op. cit., p. 376, pi. ccclxxi, figs. 3, 4 ; Pictet and Campiche, op. cit., 
p. 101, pi. cvii, figs. 2, 3. 



ANATINA. 239 



Anatina (Cekcoxiya) (iriiciTis, ricfft and Cdm/iirln', 18()5. Plato XXXTX, figs. 2 — 4. 

1855. Anatina 'RoTiivsxi.intiK. F. J. Pidet and E. Renevier. Foss. Terr. Aj/tii'ii 

(Mati'r. Pal. Suisse, ser. 1), p. 63, pi. vii, li>,'. 1. 
(Nou A. Robinaldina , d'Orbigny, 1845.) 
1865. GURGiTis, F. J. Pictet and G. Campiche. Fo.ss. Terr. Cri't. Ste. 

Croix (Mat('r. Pal. Suisse, ser. 4), 
p. 105, pi. cvii, figs. 6—8. 
1870. — (Cercomya) GDRGiTis, J'. <S7o/iC2/.-a. Palaeont. Iiiilica, Cn-t. Fauna 

S. ludia, vol. iii, ji, "4. 

Description. — Shell elongate, compressed, inequilateral, highest in front of the 
umbones, tapering posteriorly. Anterior margin rounded. Urabones incon- 
spicuous, with a carina extending to the postei'ior extremity. A very shallow 
siilcus passes from the umbo obliquely forwards across the valve. In front of this 
sulcus the ornamentation consists of narrow, sharp, concentric ribs separated by 
broad interspaces ; both ribs and interspaces are crossed by numerous radial rows of 
very small pointed projections. Behind the sulcus the concentric riljs become less 
distinct or represented by growth-rings only. 

Affinities. — This species is allied to A. (Cercomya) Bohinahliua, d'Orbignj-,' but 
the posterior pai"t of the shell is more elongate. 

Bemarl's. — I have seen only three examples of this species. Pictet and 
Campiche state that the part of the shell just in front of the carina is ornamented 
with radial rows of punctate striae ; these are not seen on the English specimens, pro- 
bably on account of their somewhat imperfect preservation. One of our specimens' 
(Plate XXXIX, fig. 3) agrees very closely, both in the form of the .shell and in the 
character of the ornamentation, with the figure given by Pictet and Renevier; the 
others (figs. 2, 4) approach more nearl_y the examples figured Ky Pictet and 
Campiche, but the anterioi* part of the shell is rather higher. 

Tupe. — From the Aptian of the Pcrte-du-Rlione. 

Distrilmtion. — Lower Greensand (Crackers) of Atherfield. 



Anatixa (Cercomya), sp. Plate XXXIX, fig. oa, h. 

Description. — Shell very long, compressed, considerably inequilateral, highest 
in front of the umbones; posterior \r,\v\ tapering, and curved upwards. Anterior 
margin rounded; venti-d niai'gin convex; pcstero-dorsal margin concave. Um- 
bones curved posteriorly, with a carina and a shallow furrow extending to the 

1 ' Pal. Franc. Terr. Crct.,' vol. iii (1845), p. 374, pi. ccclxx, figs. 6—8. 



240 CRETACEOUS LAMELLIBRANCHIA. 

postei-iiir I'-xtrt'iuity. On the anti'i'ior part of the sIil'U the (ii'iiaiiieutatiuii consists 
of narrow, sliarp, concentric ribs, ■\vliicli become less distinct on the median and 
posterior parts. 

Bemiiiis. — Only one specimen — an internal cast — has been seen. Tt i-esembles 
A. (Gercumija) riii.ri/ifl>i, but is more inequilateral and more elongate. 

DistriJjutioii. — Upper Greensand of the Isle of Wight. 

Anatixa (Ckkcomya), sp. Plate XXXIX, fig. C. 

Imperfect specimens of a species of Anatina {Gercomya) have been found in the 
Upper Greensand of Warminster and in the Cenomanian (Bed 10) of Dunscombe, 
South Devon. In shape they resemble A. {Gercomya) fvoiliirtu, Zittel.^ 

Genus — Thuacia, Leach in //. M. 1). de Blaiiivilh', 1824. 
(' Diet. Sci. nat.,' vol. xxxii, p. 347.) 

Thhacia PuiLLiPsi, lidmer, 1841. Plate XXXIX, figs. 7— U. 

1829. Mya depressa, J. Phillips. Geol. Yorks., p. 121, pi. ii, fit;. 8 (uou M. depressa, 

Sowerbv, 1823). 
1841. Thracia FHihhipsii, F. a. Bljmer. Die Versteiu. d. uord-deutsch. Kreide- 

geb., p. 74, pi. X, fig. 1. 
1850. — RBCVRVA, A. (VOrhiijiiy. Prodr. de Pal., vol. ii. p. 117. {'f T. snb- 

(lepressa, p. 74.) 
1854. — Phillipsi, J. Morris. Cat. Brit. Foss., ed. 2, p. 227. 

1865. — — F.J.PictetamlG.Gampiche. Foss. Terr. CrJt. Ste. Croix 

(Mater. Pal. Suisse, ser. 4), p. 120. 
— — EECURVA, Picfet and Ganqnche. Ibid., p. 120. 

1870. — — F. Stoliczka. Palaeont. ludica, Cret. Fauua S. India, 

vol. iii, p. 72 {Corimya V). 
1875. — Phillipsii, Phillips. Op. cit,, ed. 3, p. 254, pi. ii, fig 8. 

1900. — Phillipsi, A. Wdllemann. Die Biv. u. Gastrop. d. deutscli. u. 

liolliind. Neoeoms (Abliaudl. d. 
k. preussisoli. geol. Land., n. f., 
pt. 31), p. 139, pi. vi, fig. 6. 
1905. — — E. Harborf. Die Faima d. Seliauiuburg-Lippe"sclien 

Ivreidemulde (ibid., pt. 45), p. 77. 
1908. — — WoUemaiiH. Jalirb. d. k. preuss. geol. Laudesaust., 

fiir 1908, vol. xxix, p. 16tj. 

Description. — Shell thin, more or less ovate in outline, moderately convex, the 
right valve a little more convex than the left, slightly inequilateral. Antero-dorsal 

1 ' Die Bivalv. d. Gosaugeb,,' pt. 1 (1864), p. 10 [114], pi. i, fig. 6. 



THRACIA. 241 

margin nearly straight, Avitli a considerable ventral slojie ; anterior margin rounded, 
passing gradually into the convex ventral margin ; posterior margin rather short, 
oblique, more or less truncated, forming a rounded angle with the nearly straight 
and veutrally sloping postero-dorsal margin. Umbones rather prominent, curved 
inwards and slightl_v backwards. Postero-dorsal part of valves cduipresseil, some- 
times with a small cariiui. Surface with numerous small concentric growth-ridges. 
Measiir<'inenfti .■ 

(1) (2) (3) 

Length . 68 . 64 . VJ mm. 

Height . 52 . 4(i . :38 „ 

Thickness . 30 . 28 . 22 „ 

(1—3) Speetou. 
Affinities. — It is probable, as maintained by Harbort,' that Thracia striata, 
Weerth,- is not specifically distinct from 7'. I'liillipsi. 

Bemarls. — The greater part of the shell has disappeared from most of the 
examples found at Speetou, and usuall}- some part of the margin of the cast has 
also been lost. I have not seen sufficient examples to enable me to determine 
whether the variation of this species in England is as great as in the case of the 
specimens found in Schaumburg-Lippe and described by Harbort. 
Ti/jte. — From Speetou, in the York Museum. 
Distribution. — Speetou Clay (zone of Belemnites Jacitlnm) of Speeton. 

Tiii;\ciA ROTUNDATA (So^vrA//), 18:56. Plate XXXIX, fig. M).i,b. 

1836. Panop^a ROTUNDATA, /. de C. Soirerhij. Traus. Geol. Soc, ser. 2, vol. iv, 

■ pp. 129, 337, pi. xiu, fig. 2. 
1850. Lyonsia sdbbotundata, A. trOrbUjnij. Prodr. de Pal., vol. ii, p. 74. 
1854. Myacites eotundata, /. Morris. Cat. Brit. Foss., ed. 2. p. 214. 
1865. Thracia subrotundata, F. J. Pirtct and G. Cnnqiiche. Foss. Terr. Cret. 

Ste. Ci-oix (Mat'.'r. Pal. Suisse, ser. 4), p. 120. 
1870. CoRiMYA ROTUNDATA, F. Sloliczlca. Palscout. Iiulioa, Cret. Faima S. ludia, 

vol. iii, p. 72. 

Description. — Shell regularly convex, oval, slightly iuc'(|uivalv(' and iniMpiilateval. 
Anterior an<l ventral margins convex, forming a regular curve. Dorsal part of 
posterior margin ol)lique, forming an angle with the ventral part. Umbones broad, 
in contact, with a narrow, sharp, curved carina extending to tlie posterior angle 
and limiting a triangular, concave, postero-dorsal area, which is ornamented with 
fine ribs running parallel to the posterior margin. Sides of valves with similar 
ribs extending in a radial direction. 

^ 'Die Fauna d. Schauiiiburj.c-Lippe'sclieu Kreideuiulde ' (1905), p. 78. 

= 'Neocomsundst. im Teutolmrg. Waldo" ('Pala-ont. Aliliaiidl. ' II, 1884), p. 40, pi. viii. fii,'. 10. 
Wollemaun, ' Die Bivalv. u. Gastrop. d. deutsoli. n. liolliiud. NeoL-oins ' (1900), p. 1 40, pi. vii, fig. 1. 

32 



(1) 


(2) 


40 


32 iiini. 


32 


07 

-J' „ 


oo 


17 



242 CRETACEOUS LAMELLIBRANCHIA. 

Measurements : 

Length 
Height 
Tliickness . . 

(1. L* ) Lviujilie. 

Affinities. — This species is allied to T. rutinul't, J^ictet iuid Roux,' from the 
Gaiilt of the Perte-du-Rhune and Sainte Croix, Ijut is distinguished by its more 
rounded outline, smaller postero-dorsal area, and less distinct concentric ornament. 
It is also allied to T. carinifern (p. 244). 

Bemarls. — Two internal casts of this species from Lympne are in the Museum 
of Practical Geology (23470, 23471) ; the larger agrees closely with Sowerby's 
figure, and may perhaps be the type, but the locality given by Sowerby is Court- 
at-Street, 1^^ miles west of Lympne. A small, somewhat crushed example from 
the Atherfield Clay at Dover colliery probably l)eIongs to this species. No other 
specimens have been seen. The specimens recorded by Topley as 7'. riiriinfcrn 
probably belong to T. rotiinJata. 

Disfriliiitioii. — Hythe Beds of Lympne and Court-at-8treet.- 

TuKAi'iA RoiiiNALDiXA r {(V Orhiijii i/), 1845. Plate XL, figs. 1 — 3. 

Descri2)tioii. — Shell oval, nearly equilateral ; I'ight valve more convex than 
the left; posterior part not (juite so high as tlie anterior part ; postero-dorsal \)avt 
compressed. Anterior margin rounded; ventral margin moderately convex; 
posterior margin slightly curved ; postero-dorsal margin nearly straight. Umbones 
rather prominent, curved posteriorly. Surface smooth, except for growth-lines. 

Measurements : 



Length 
Height 
Breadth 



(1) 


(2) 


(3^ 


36 


26 


15 mm. 


23 


17 


„ 


13 


10 


c. „ 



(1) Penia-hed. (2, 3) Crackers, Atherfield. 



Remarls. — In the English specimens, which are here provisionally referred to- 
T. h'iihlniikliiHi, the shell is jireserved, but the examples of that species figured l)y 
d'()i'l)igny^ and by Pictet and Campiche' are internal casts, and it is consequently 

' ' Moll. Foss. Grcs verts de Greucve ' (1852), p. 414, pi. x.xix, fii,'. (3. Pictet and Campiche, ' Foss. 
Terr. Cret. Ste. Croix' ('Mater. Pal. Suisse,' ser. 4, 1865), p. 117. 

- Thracia Nieoleti (Agassiz) has been recorded by Morris and by Topley Iroiu the Hythe Beds of 
Hythe, but I have not seen any British examples of that species. 

3 ' Pal. Frau9. Terr. Crct.,' vol. ili (1845), p. 380, pi. ceclxxii, figs. 1, 2. 

■' 'Foss. Terr. Crct. Ste. Croix' ('Mater. Pal. Suisse,' ser. 4, 1865), p. 114, pi. cviii, figs. 5, 6. 



THRACIA. 243 

(lifRcult. especially without the opportunity of comparing specimens, to establisli 
the identification. Professor Boule informs me that the type is a poorly preserved 
specimen, but that its outline is satisfactorily represented in (rOi'bio-ny's fio-ure; 
the specimen is now in tJie Natural History Museum, Paris. T. Iu>huuihlina is 
allied to T. mocomiensls (d'Orbigny),' but is said to differ from tlic latter l)y the 
greater curvature of the ventral margin and by its relatively sliorter shell. 

Distrihatiou, — Lower Greensand (7V/;/r(-l)cd and Crackers) of Atherfield. 
Atherfield Reds of Redhill, Reigate. 

'i'iii;A('iA Sano'X\e-Crucis, ridet civd Cdnqiirln-, 18()5. Plate XL, tigs. 4 (i. 

1865. Thracia SANCTiE-CRrcis, F. J. Pirli^t ami G. Campirh,-. Foss. Terr. Crot. 

Ste. Croix (Mater. Pal. Suisse, ser. 4), 
p. 117, pi. cviii, fio-. 8. 

1870. — — F. Stoliczht. Palseont. Iiulica, Cret. Fauna S. 

India, vol. ill. p. 72. 

Description. — Shell oblong, compressed, inequilateral. Anterior margin 

rounded; ventral mai'gin slightly curved; posterior margin truncated, slightly 

convex, forming an angle with the postero-dor.sal margin. A carina e.xtends in a 

curve from the umbo to the postero-ventral angle and cuts off a concave postero- 

dorsal area. The surface of the shell is ornamented with growtli-rings. 

Measurements : 

(1) (-') 

Length . . 43 . 3'.) mm. 

Height . . 20 . Ki „ 

(1) Gault, Folkestone. 

(2) Gault, Black Veu. 

Aijiuih'ea. — It seems doubtful whethei- this species is distinct from 2\ siviplex 
(d'Orbigny), of which casts only are figured by d'Orbigny- and by Pictet 
and Campiche^; but the latter authors state that it differs from T. siuqilcr by the 
absence of an internal rib, the })resence of a carina, and by the more acuminate 
anterior end. 

Ti/jye. — From the LTpper Gault of Ste. ('roi.\. 

I >isti'iliiiti(iii. — Gault of Folkestone and iJlack ^'en. 

Tiii;.\(iA, sp. i'late .\l>, figs. 7 — '.». 

Some examples of Tlinicia, usually of rather large size, apjiear at first .sight to 
be distinct from T. Smicfie-Gritcis on account of their i-elatively greater height and 

1 'Pal. Frane. Terr. Cri't.,' vol. iii (1845), p. 381, pi. cei-lxxii, fi>.;s. 3, 4. Pictet aud Cauipiche, 
op. cit., p. 11-5, pi. cviii, fij^s. 3, 4. 

- Op. cit., p. 382, pi. ecelxxii. flip's. .5, ti. 

8 ' Foss. Terr. Crc't. Ste. Croix " (' Mater. Pal. Suisse,' ser. 4, 1865), p. 116, pi. iviii. fii;. 7. 



2U CRETACEOUS LAMELLIBRANCHIA. 

less distinct carina. When, however, a consideral)le nunil)er of specimens are 
compared it is difficult to draw any line of separation between these forms and T. 
Sanctse-Crucis. But since, in most cases, the original shape of the shell has been 
more or less considerably modified l)y pressure, it is not easy to come to a definite 
conclusion in this matter; moreover, in botli 7'. Sa)ictas-Grucis and the larger forms 
there is clearly some variation in relative heii^'lit and length of the sliells, and in 
the distinctness of the carina.^ 

JJistribidio)!. — Gault of Black Yen and Folkestone. Upper Greensand of 
Blackdowu and Devizes. 



Thracia CARiNiFEifA {Soivevhi/), 182(). Plate XL, figs. 10 — 13. 

182(j. LuTEARiA r CAEiNiFERA, /. lie C. Soivefhy. Mill. C'oiuli., vol. vi, p. 66, pi. 

dxxxiv, fig. 2. 
1832. • — —A. Passij. DescTipt. gi'ol. tie la Seiue-Iiift'r., 

Atliis, \>. 6, pi. xiii, figs. 6, 7. 
1842. CoBiMYA CARINIFEKA. L. Ayassiz. Etudes crit. Moll. Foss., Myes, p. 264. 
1845. Lyonsia carinifera, A. d'Orhiijni/. Pal. Franc. Terr. Crct., vol. iii. p. 385, 

pi. eeelxxiii, figs. 1, 2. 
1850. — —A. cVOrblijiiy. Prodr. de Pal., vol. ii, p. 158. 

1852. — — A'. Ktier. Deukschr. d. k. Akad. d. Wisseiiscli. Wien, 

Math.-uat. CI., vol. iii. p. 311. 
1854. LuTEARiA CARINIFERA, /. Morfis. Cat. Brit. Foss., ed. 2, p. 208 (r Thracia). 
1865. Thracia carinifeka, F. J. Pictet aitd G. Campiche. Foss. Terr. Cret. Ste. 

Croix (Mati'r. Pal. Suisse, ser. 4), p. 121. 
1870. — — F. Sfuliczht. Palaeout. ludiea, Cret. Fauua S. ludia, 

vol. iii, p. 72. 
1893. Lyonsia carinifera, .4. Fc(7i?(7i. Stud. imGebietederbiJhru. Kreideformat. 

V. Prieseii. Si-liiclit., p. 97, fig. 115. 

Description. — Shell thin, oval, of moderate cunve.xity, slightly inequivalve and 
inequilateral. Anterior margin rounded, jjassing gradually into the reguhirly 
convex ventral margin. Posterior margin truncated, straight or slightly concave. 
Postero-dorsal margin nearly straight. Umbones In'oad, incurved close together, 
with a sharp carina passing to the postero-ventral angle and limiting a flattened 
or slightly concave postero-dorsal area, whieh is tlivided in the middle l)y a shallow, 
longitudinal fnri'ow. -lust in front of the carina is a broad, shallow, concave 
depression. 

Ornamentation consists of broad, slightly raised, concentric folds Avhich are 
more distinct on the anterior part than elsewhere. On the postero-dorsal area are 

^ A similar case of distortion and variation is i'urnislied liv Thracia semijilanata, Whiteaves, 
' Mesozoie Foss.' (' Geol. Surv. Canada'), vol. i (1884), p. 221, pi. xxix, fig. 5. 



PHOLADOMYA. 245 

nimiorous, fine, regular ribs parallel with the posterior margin ; on the remainder 
of the shell similar ribs, but running in a radial direction, occui-. 
Measurements : 

(1) (2) (3) (4) 

Length . . 37 . 88 . 30 . 20 mm. 
Height . . 23 . 22 . 21 . 1-t ., 
Thickness . 15 . 14 . — . 10 „ 

(1) Chalk Marl, Chard. 
(2, 4) Chloritic Marl, Devizes. 
(3) Chalk Marl, Ventiior. 

Abilities.— In this species the shell is more elongate and less convex, the carina 
more prominent, and the postero-dorsal area larger than in T. mf inula fa (p. 241). 
T. carinifera is closely allied to T. I'lcgmis (d'Orbigny),' froni the Cenomanian of 
St. Sauveur, l)ut is less elongate. T. German (Greinitz)- from the Senonian, is 
regarded by Bi-auns'^ as a synonym of T. carinifera ; but without seeing specimens 
of the former it is ditlicult to express an opinion of its relationship. 

licmarls. — The specimens vary considerably in the pro])ortion of leiigtli to 
height, but in some cases the differences are probably due partly to crushing. 
The shell itself is seldom preserved. 

Type. — The type came from the Cenomanian of Dowlands (South Devon) and 
was originally in the collection of Sir H. T. De la Beclie, but cannot now l)e 
found. 

Distribution. — Chloi'itic Marl of Devizes and Maiden Bradley. Chalk .Marl of 
Veutnor, Evershot, and Chard. 



i^am%— PHOLADOM YJ D^¥., (Iraij. 

Genus — Puoi-.viH>MY.\, (/. B. Soice,ii/, 1825. 
(' Genera Eee. ami Foss. Shells,' uo. xix, pi. .x.xxvii.) 

Phol.\.domv.v Cok.nuki.iax.v {(VOrliiij)iii), 1844. Plate XLT, figs. 2'/,//, '■\. 

1844. Cabdium CouNUELiANUJi, A. d'Oihi(jiiij. I'al. Frauc. IVrr. Crt't., vol. iii, 

p. 23, pi. cclvi, figs. 1, 2. 

1845. — — E. Forbex. Quart. Jourii. Greol. Soc, vol. i, p. 243. 
1850. Pholadomya Cornueliana, A. crOrhiijiiy. Prodr. ile Pal., vol. ii, p. 117. 
1854. Cardium Cornuelianum, /. Morris. Cat. Brit. Foss , ed. 2, p. 192. 



1 'Pal. Fran9. Terr. Crct.,' vol. iii (1845), p. 386, pi. ccclxxiii, figs. 3 — 5. 
- ' Quaiiersandst. oder Kreidegeb. in Deutschlaud ' (1850), p. 150, pi. x, figs. 9 — 11. 
* ' Seuon. Mergel d. Salzberges,' Zeit.schr. f. d. gesammt. Naturwiss., vol. xlvi (1876). p. 35!'. pi. x, 
figs. 18, 19. 



246 CRETACEOUS J.AMELLTBRAXCHIA. 

18o5. Pholadomya Cornueliana, F. J. Pirtet and E. Renevier. Foss. Terr. Ajitieu 

(Mati'r. Pill. Suisse, ser. 1), p. 59, pi. vi, fi>;. 6. 
1865. — — F.J.PictetandG.Campiche. Foss. Terr. Grot. 

Ste. Croix (Mater. Pal. Suisse, ser. 4), p. 87. 
— — — H. Coquaiul. Aptien de I'Espague, p. 93. 

1870. — — F. Sloliczka. Palsont. ludica, Cret. Fauua S. 

Imlia, vol. iii, p. 75. 
1875. — — G.Moesch. Mou. PliolacIom_ven,p. 96, pi. x.xxiii, 

fig. 8 (ypl. xxxvi, fig. 4). 

iJi'scriptioi). — Shell .small, .sliurt, oval, inflated, conijiressed posteriorly, 
moderately ine([uilateral with a small gape at the posterior end. Margins rounded. 
Umbones prumiiient, incurved. 

Ornamentation consists of strong, ronndcd, radial I'ibs. The grooves between 

the i'il)s are shallow, and broader than the ribs. Concentric riljs cross the grooves 

and ribs, giving to the latter a granulate or tuberculate api)ea)'ance. Near tlie 

posterior and anterior mai-gins radial ribs are absent. 

Mc(t!inri')iU'iifs : 

0) (2) 

Length . . 20 . . 1:1 mm. 

Height . . 10 . K) „ 

(1, 2) Atherfieia. 
Ajji iiitii'K. — This species reseml)les P. Saurtl-SdJix (Rdmer)' from Texas and 
/'. ]'iij)tP!<i, Lartet,'- from I'alestine, Syria, and Zululand, and 1'. siilxliiuni.'^i.i 
(d'Orl)igny),'^ from the ( 'enomanian of Le Mans. 

7'///>e. — From the Aptian of Was.sy (Hante-Marne). 

Dtstribtttloii. — jjower (Jreensand (Crackers) of Atliertield. Recorded by Topiey 
from the Atherfield Beds of Peasemar.sli and Shalford. 

i'lKH.AiioMVA (MCAxri-A {S<Hr>'rhi/), IS'Ml i'late XL, tig. 11; Plate XLl, fig. 1. 

1708. C. N. LatKj, Hist, lapidum tiguratonmi, p. 146, pi. xliv, tig. 1. 
1718. J. J. Scheuchzer, Helvetiae hist, uat., pt. 3, p. 307, fig. 113. 
1742. L. Bourguet, Traitc des Petrific, pi. xxiv, fig. 145. 



1 • Kri'idfliilil. V. Texas' (1852), p. 48, pi. vi, fig. 7. F. CormifJiana has heeu compared with 
Corbiihi wquivalvU, Cxoldfuss, by Pictet and Reuevier, Pictet and Campit-he, and Moesoh, but HolzaptVl 
has shown that Goldfuss' species belongs to the genus LiopiMa. Holzapi'el, ' Die MoUusk. Aicheu. 
Kreide ' (' Palseontographica,' vol. xxxv, 1889), p. 150, pi. ix, figs. 4 — 6; Miiller, ' Mollusk. d. Untersenon 
v. Braunschweig u. Ilsede ' (1898), p. 76, pi. x, fig. 9. 

- 'Explor. gcol. de la Mer Morte ' (1877), p. 126, pi. xi, fig. 9; BlancUenhorn, ■ Beitr. z. Geol. 
Syriens' (1890), p. 94, pi. v, figs. 14—17; Kossmat, ' Deukschr. d. k. Akad. Wiss., Wien,' vol. Ixxi 
(1902), p. 55, pi. iv, fig. 9 ; Newton, ■ Trans. Roy. Soc. S. Africa,' vol. i ( 1909), p 79, pi. vi, figs. 3—6. 

•' ' Pal. Franc. Terr. Cret.,' vol. iii (1844), p. 38, pi. eel. figs. 1—3. An internal east resembling 
P. t^iiliiliiieiisiK has been found by Mr. J. Scaues in the C'hloritic Marl of Maiden Bradley. 



PHOLADOMYA. 347 

1836. PHO.AS OXC......S, /. ,e C. So..erl,j. Trans. Geol. Soc. ser. 2. vol. iv. ,,,. 

184.0 T3 130, 338. pi. xvi, fij;. 1. 

1840. PHO...OM.. ..o.o.r.,A. G.Iclf.ss. Pefof. Genu., vol. ,i. p. 27U. pi. 

1840 __ >^^^'''' fig- 3- 

~ ^-^'J^^^tz. fitudes crit. M„ll. Foss., Myes, p. 57, 
pi. i. fit,'s. IC. 17. 

- SCHEUCHZERI, Aya,,h. lhh\., p. .58, p|. iil. fi.s. 3- 7, pi. iiil 

%'■ 7. 

— Favrina, .'(j/a.v.s/r. Iliid., p. .59, pi. iil, fi^,,s. 1, 2. 

- - L.VNGII, To//., i„ Z,.y„,,,,v. Mem. Soc. gJol.de France, ser. 2, 

1845 '■"'• ''• P- 24- 

ELONGATA, ^. ,rO,i/,/„^. Pal. Franc. Terr. Cret., vol. iii, 

_ p. 350, pi. ccclxii. 

lo,n GiOANTEA, E. Forbes. Quart Jouru. Geol. Soc, vol. i, p. 238 

180U. _ ELONGATA, cWrbiyny. Prodr. de Pal., vol. ii, p 73 

Faveina, F. J. Pictet „,ul W. Bo,u: Moll. Foss. Gr^-s verts 
10.A. '^'' Geneve, pp. 403, 546, pi. xxix. fijr. 1 

l«?t ~ «i«ANTEA. /. 3I„n-h. Cat. Brit. Foss., ed. 2, p ooq 

_ ~ ELONGATA. G. CW.„„. Moll. Foss. de ITonne. p. 55. 

— F. J. Pictet a„(l E. Renevier. Foss. Terr. Aptieu 
185g _ , (Mater. Pal. Suis.se, ser. 1), p. 61. 

— J.rUaiwva.y.Piera. Mem.geog.-agric. de Castellon. 

1861 -_ ^''' "'' ^°- ^*'- 

1864— or _ ~ P-de Loriol. Anim. Invert. Foss. Mt. Sali-ve, p. 56. 

~ ~ F-J-Pi<-tetan(lG.Camiiiche. Foss. Terr. Crt't. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), 

lr.7A !'• ""*■ P'- ^■''■' fi^'**- 1— *• 

- GiGANTEA et ELONGATA, F Stoliczka. Pateont. Indica, Cret. 

-loyt- Fauna S. India, vol. iii, p. 7f. 

^^- ~ GIGANTEA, C. Moescli . Mon. Pholadoniyen, p. 82, pi xxx. fig. 



6 : pi. xxxi, figs. 2- 

1»»4. _ cf. GIGANTEA, 0. Wcnth. Die Fauna des Neoeoni. im Teuto- 

burg. Walde (Palaeout. Abhandl., vol. ii), 
P- 34, pi. viii, figs. 2, 3. 
^^^- ~ Weerthii, F. Vocjel Hollaudiseli. Kreide. p. 5H. 

— — ELONGATA. G. Maa,. Zeifsehr. d. deutsch. geol. GesellscL.. 

~ — -A- Wollemaiu,. Ibid., vol. xlviii. n 850 

~ — ^. TFo/?e»(((««. Die Biv. u. Gastrop. d. deutsch. 

u. holliiud. Neoconis (Abliaudl. 
d. k. preussiscli. geol. Laud., 
N. F., pt. 31), p. 133 
~ ~ — G. Mailer. Deutscli-Ost-Afrika, vol. vii, p. 557, 

1>1. xxi, fig. 1. 
^^^^- ~ ~ G. Binchhavilt. Palipontographica, vol. 1, ],. 7.;. 

pi. XV, figs. 1, 2. 

*^'^' ~ —A. Stojanoff. Ann. gc'ol. et niin. de la Eussie, vol. 

X, p. 111). 



248 CRETACEOUS LAMELLIBRANCHIA. 

Description. — Sliell large, eloniifate, some what arched, convex, l)ut with tlie sides 
of the posterior part more or less flattened, very ine(|uilateral, with a large gape 
at the posterior end. Anterior part short, with a rounded margin. Venti'al margin 
curved. Posterior margin sul)truncate, roiuukcl. Po.stero-dorsal margin long, 
slightly concave or almost straight. Umbones broad. Near the nnd)ones the 
antero-dorsal and postero-dorsal marginal parts of the shell are depressed. 

Ornamentation consists of numerous narrow, sharp, prominent and sometimes 
slightlj- serrate radial ribs, which are straight or slightly curved. Near the 
anterior and the postero-dorsal mai-gins ribs are absent ; on the postero-dorsal part 
of the shell they are rather inore widely separated and i-ather more jn-ominent 
than on the median ])art. Between the ribs are broad, concave fun-ows wliicli aie 
crossed by numerous growth-lines. 
Measiivfments .• 

(1) (2) 

Length . . 12() . 122 mm. 

Height . . 63 . GO „ 

(1, 2) Crackers, Atlierfiekl. 

Jljiiiitirs. — The elongate form and numerous sharp ribs distinguisli tliis from 
other Cretaceous species of Plioladomi/a. 

lii'niarls. — The foreign examples of this species show considerable vaiiatii)ii in 
length, in the curvature of the shell, and in the nuiuber of ribs. Some of the 
varieties have been described as distinct species, but Pictet and Campiche have 
shown that there are numerous transitions between the different varieties. The 
English examples agree in most cases with the type of the species, but some 
ajjproach the variety described by Agassiz as P. Scheuchzeri. A specimen figured 
by Moesch shows the large pallial sinus. 

Ti/pe. — The type came from the HytheBedsof Court-at-Street, but cannot now 
be found. 

Distfibufioii. — Lower Greensand (Crackers) of Atherfield. Atherfield Beds of 
East Shalford. Hythe Beds of Court-at-Street and Lympne. 

Puor.AiioMVA si'KKTONENSis, sp. uov. Plate XLT, fig. L', A. 

Description. — Shell large, oval, short, intlated, very inecpiilateral. Anterior 
margin rounded; ventral margin convex. Umljones broad, incurved. 

Ornamentation consists of numerous (usually about twenty-one) strong, radial 
ribs, separated by broad, slightly concave interspaces. Secondary ribs are iiitru- 
duccd at a short distance from the umbo, and usually soon become as large as the 
])riniary ribs. The ribs are more or less nodular. Concentric growth-lines are 
present. Two or three of the anterior ribs are more widely separated than the 
others. On the postero-dorsal and the anterior parts of the shell ribs are absent. 



PHOLADOMYA. 249 

Affinities. — By some autliors tliis species has been identified with P. Martini, 
Forbes. With the matevial at present available it is difficnlt to make a satisfactory 
comparison ; but the specimens from Speeton are of considerably larger size, with 
broader and less prominent nmbones, and with the posterior part of the shell less 
compressed than in P. Martini. 

In form tliis species resembles P. alternans, Roraer,' l)ut tlie nmbones are 
relatively higher, and the radial ribs more numerous. The ribs arc not so numerous 
as in P. Eherfi, Wollemann." 

EemarJi:s. — The specimens from the clays are considerably crushed, whilst in 
those from the hard nodular beds a more or less considerable portion of the 
marginal part of the shell is missing. 

Difiribntion. — Speeton Clay (zones of Bclenmites lateralli, B. jaculnni, and B. 
bnmsvicensis) of Speeton. 



PuoLAUO.MYA M.vitTixi, Forbc-^, 18-t-j. Plate XLI, tig. o. 

18i5. Pholadomya MiRxiNi, E. F.jrhe.-!. Quart. Jourii. G-aol. Soc, vol. i, p. 233, 

pi. ii, fit;. 3. 
18-50. — — A. d'Orhhpi;/. ProJr. (le Pal., vol. ii, p. 117. 

1854. — —J. Morris. Cat. Brit. Poss., ed. 2, p. 220. 

1865. — —F.J. Piclet and G. Campiche. Foss. Terr. Crct. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), p. 92. 
? 1908. — — A. Wollemanii. Jahrb. d. k. preuss. geol. Laudes- 

anst. fiir 1908, vol. xsix, p. 165, 
pi. X, fig. 3. 

Description. — Shell rather small, oval, very inequilateral, anterior part inflated, 
posterior part compressed. Unibones prominent. Escutcheon, deep. Ornamenta- 
tion consists of numerous radial riljs, which are more or loss tu))erculate, and ai-e 
more widely separated anteriorly than on the median part ; on the anterior and 
postero-dorsal parts ribs are indistinct or absent. Concentric ribs and growth-lines 
are present. 

Remarks. — It is difficult to give a satisfactory description of this species, since 
the specimens seen are few in uuiuber, imperfectly preserved, and usually crushed. 
P. Martini appears to be closely allied to P. Fahrimi, d'Orbigny (see below). It 
also resembles P. hispanica, Coquand."' 

1 Wollemaun, ' Die Biv. u. Gastrop. <1. dcutsch. ii. liolliimliscli. Neocoms' (1900), p. 134, pi. v, figs. 
9, 10 ; pi. vi, tig. 3. Speeiineus with fewer ribs from the Spilsin- Saudstoue aud the Claxbv Ironstone 
of Lincolnshire approach P. alteniaiii more nearly than do the specimens from Speeton. 

2 Il)i.l., p. 136. pi. vi, fig. 4. 

3 'Mou. Aptien de I'Espague' (1865), p. 92, pi. vii, figs. 5, 6. 

33 



250 CRETACEOUS LAMELLIBRANCHIA. 

Type. — From the Hytlie Beds of Piilborongli . A specimen which is believed to 
be the type, but wliich is more crushed dorso-ventrally than is indicated by the 
figure, is in the Museum of the Geological Society (No. 2197). 

Distribution. — Lower Greensand {Perna-heA and Crackers) of Atherfield. 
Hythe Beds of Pnll)orough. 

Pholadomya Fabuina, (VOyhiijinj, 1845. Plate XLI, fig. G. 

1845. Pholadomya Fabrina, A. d'Orbiyny. Pal. Fran9. Terr. Crt't., vol. iii, \>. 

354, pi. ccclxiii, figs. 6, 7. (Non 
P. Favrina, Agassiz, Pictet and 
Roux.) 
1850. — — d'Orbigny. Prodr. de Pal, vol. ii, p. 135. 

1865. — — F.J. Pictet and G. Campiche. Foss. Terr. Crct. Ste. 

Croix (Mak'r. Pal. Suisse, ser. 4), p. 92. 
1897. — Favbina?, B. B. Newton. Proc. Dorset Nat. Hist, aud 

Antiq. Field Club, vol, xviii, 
p. 92. 

? Non 1874. — Fabbina, C. Moe.n-Ji. Mon. Pholadomyeu, p. 94, pi. xxxii, fig. 1. 

RemarJis. — Some crushed specimens found in the Gault are probably examples 
of P. Fabrina, d'Orbigny. They resemble P. Marti iii, but have coarser and more 
distinctly tiiberculate ribs, and the concentric rings appear to be more conspicuous. 

Distribution. — Gault of Black Ven, Okeford Fitzpaine, and Folkestone. 

Pholadomya decussata (Muntell), 1S22. Plate XLI, figs. 7—9; Plate XLII, fig. 1. 

1822. Cabdium ? DEcussATUM, G. Mantell. Foss. S. Downs, p. 126, pi. xxv, fig. 3. 
1827. — — /. de C. Sou-erhy. Miu. Conch., vol. vi, p. 99, pi. 

dlii, fig. 1. 
1837. — — A. Gold/uss. Petref. Germ, v.il. ii, p. 222,pl. cxlv, 

fig. 2. 

— Pholadomya decussata, G. G. Pitsc/i. Polens Paliiout., p. 87. 

1841. Cardium DECUSSATUM, F. A. Rijmer. Die Versteiu. d. uord-deutsch. 

Kreidegeb., p. 71. 
1846. Pholadomya decussata, A. E. Beuss. Die Verstein. der bohni. Kreide- 

format., pt. 2, p. 17. 
1850. — — J. de C. Sorverhy,'mF. Dixon. Geol. Sussex, p. 355 

(p. 385, ed. 2), pi. xxix. fig. 6. 

— — — H. B.Geiiiitz. Das Quadersaudst. oder Kreidegeb. 

in Deutschlaud, p. 146. 

— — — J?. Kiier. Yerstein. d. Kreideniergels v. Leniberg 

(Haidinger's Naturwiss. Abhaudl., 
vol. iii, pt. 2), p. 24. 



1869. 



1876. 



PHOLADOMYA. 251 

1850. Pholadomya decussata, A. AW,. Geogu.-pateont. Bescbreib. v. Lemberg 

(ibid.), IX 236. 
^^^^- ~ —J. Morris. Cat. Brit. Foss., ed. 2, p. 220. 

^^*'^- — — var. TRixaavhARiH, H. G. Seeley. Anu.Mag.Nat. 

Hist., ser. 3, vol. vii, p. 122. 
1863. — (CARmvM.)DECvsaArA, A. v.Stromheck. Zeitschr. der deutscb. 

geol. Gresellscb., vol. xv, p. 143. 
1865. — DECUSSATA, F. J. Pictet and G. Campiche. Terr. Cret. Ste. 

Croix (Matt'r. Pal. Suisse, ser. 4), p. 94. 
— — E. Favre. Moll. Foss. de la Craie de Lemberg, 

p. 106. 
1875. — _ A. J. Jukes-Browne. Quart. Joum. Geol. Soc, 

vol. xxxi, p. 300. 
~" — — C Moesch. Mon. Pboladomven, p. 107, pi. xxxii, 

figs. 5 ?, 6 ; pi. xxxvi, figs. 5, 6. 
— D. Brauns. Zeitschr. f. d. gesammt. Natm-wiss., 

vol. xlvi, p. 361. 
? 1889. — _ j;. Hohapfel. Die Mollusk. Aacbeu. Kreide (Pal- 

eeoutographica, vol. xxxv), p. 164, 
pi. xiv, figs. 3, 4. 
1891. — — J.Buhm. Kreidebildimg. d. Fiirbergs u. Sulz- 

bergs (Palseoutograpbica, vol. xxxviii), p. 73. 
1893. — — A. Fritsch. Stud, iiu Gebiete der bolim. Kreide- 

foi-mat. V. Prieseu. Sebieht., p. 97, fig. 116. 
? 1898. — — G. Mailer. Mollusk. d. Uutersen. v. Brauuscbwei" 

u. Ilsede, p. 74, pi. x, fig. 3. 
1^01. — — A. Wollemajin. Jabrb. d. k. preuss. geol. Laudes- 

aust. fiir 1900, vol. xxi, p. 22. 
1902. — -- A. Wollemanit. Liiueburg. Kreide, p. 79. 

Nou 1829. — — /. P},inq»<. Geol. Yorks., pp. 122, 186 (p. 255, 

ed. 3), pi. ii, fig. 9. 

— 1842. — — L. Agassiz. fitudes crit. Moll. Foss., Myes, p. 74, 

pi. iv, figs. 9, 10 ; pi. iv', figs. 7 — 11. 

— 1843—50. — — G. P. Desluiy:.-'. Traitc Ek'meut. de Couebyliol., 

vol. i, pt. 2, p. 158, pi. V, fig. 5. 

— 1849. — —A. (VOrhhjntj. Prodr. de Pal, vol. i, p. 335. 

Distribution. — Shell large, inflated, with the greatest diameter at the anterior 
end, outline .semi-ovate (sometimes sub-trigonal), wedge-shaped behind, extremely 
inequilateral, with a ^^nlall posterior gape; height and length often nearly equal. 
Ventral margin slightly curved. Posterior margin rounded. Anterior part of the 
shell very short, flattened, with cordate outline, nearly perpendicular to the plane 
between the valves, and forming almost a right angle with the sides of the valves ; 
the margin of the anterior part is more or less angular, and just within is a 
shallow concave part parallel to the margin, whilst the median part is convex, and 



(1) 


(2) 


(3) 


98 


60 


54 mm 


74 


59 


52 „ 


65 


51 


49 „ 



252 CRETACEOUS LAMELLIBRAXCHIA. 

that near the umboiies is depressed. Umboiies curved considerably inwards and 
more or less forwards. Escutcheon depressed. 

Ornamentation consists of narrow I'adial ribs separated hy Itroad, sliallow 
depressions. Ribs are absent from the posterior part of the shell, and from the 
anterior flattened part, except near its margin ; they become smaller or disappear 
altogether near the ventral margin. "Well-marked growth-rings occur over the 
entire surface of the shell, but are more distinct near the umbones than ventrally, 
and give a granular or nodular appearance to the radial I'ibs, especially on the 
dorsal part of the shell. 

Measurements : 

Length 
Height 
Thickness . 

(1, 2) Chalk Marl, Yeutuor. 
(3) Clialk Marl, Eastbourne. 

Affinities. — The smaller forms of this species show some resemblance to i'. 
genevensis, Pictet and Roux,^ from the Gault, but the concentric i-ings are less 
prominent, and the valves more inflated and less distinctly triangular. Another 
similar form is P. Malhosi, Pictet." See also P. cordata (below). 

The specimens from the Cambridge Greensand were regarded by Seeley as 
constituting a variety (P. derussata var. triamjularis), but, as was pointed out by 
Jukes-Browne, they agree in all essential characters with P. decussatu, differing 
only in their smaller size. Specimens of V. decussata found in the Gault of 
Folkestone are larger than those found in the Cambridge Greensand, I)ut not so 
large as the examples in the Chalk. 

Beviarks. — In England this species has not been found above the Cenomanian 
(zone of H. svh(jloI)osus), but on the Continent it appears to range up into the 
Senonian. In many of the English specimens the original shape has been modified 
l)y crushing, and that also ajDpears to be the case with some of the examples 
figured by foreign authors. 

Tj/pe. — The type from the Lower Chalk near Brighton, and the specimen 
figured by Sowerby from the Chalk Marl of Hamsey, and the one figured by 
Dixon, cannot now- be found. 

Distriltutio)!. — Gault of Folkestone. Cambridge Greensand. Chalk .Marl of 
Ventnor, Culver Cliff, Eastbourne, Hamsey, Middleham, Offham, Glynde and 
Folkestone. Totternhoe Stone (zone of Bulastcr sitbylulosux) of Arlesey and 
Burwell. 

1 'Moll. Foss. Grts verts de Gemve ' (1862), p. 405, pi. xxix, fig. 2. Moesdi, ' Mon. Pliola- 
douijeu' (1875), p. 97, pi. xxxii, figs. 2-4 

- ' Melanges Pak'ont.' (1868), p. 92, pi. xix, fig. 3. Moefecli, op. c-it., p. 88, pi. xxx, fig. 5, pi. xxxv, fig. 1. 



MY0PH0LA8. 253 



Pholadomya corpata, Tat<', 18G5. Plate XLII, fig. 2 <i — r. 

1865. PHOLADOMy.\ coEDATA, if. Tctte. Quart. Jmirn. Geol. Soc, vol. xxi, p. 4(), 

}il. iv, fii^. 1. 

BeniarliS. — A specimen fouml in the I'pper Chalk (zone of Jielemnitella mncro- 
■nata), now in the Norwich Museum (No. 3339), is probal)ly an example of P. 
cordata, Ijut unfortunately the anterior part of the shell is imperfect. In this 
species tlie anterior curvatni-e of the umbones is greater and the de2)ression in 
front of them deeper than in P. decu.ssata ; also the anterior flattened part is 
relatively smaller, since the greatest diameter of the shell occurs at about one third 
of the lengtli from the anterior end. The ty})es of P. cardata from the Upper 
Chalk of Ireland are in the Museum of Practical Geology (Nos. 23,(328 ; 28,629). 



Genus — Myopholas, H. BourilU, 1007. 

(' Bull. Soc. gcol. de France,' ser. 4, vol. vii. p. Iu7.) 

Myopholas, sp. cf. SEMicosTATA {Aijunsi::), 184-2. Plate XLIT, fig. 3//,/;. 

Descriptiun. — Shell oval, short, con.siderably ine([uilateral, anterior part convex, 
230Sterior part compressed; anterior and posterior margins rounded. Umbones 
curved inwards and forwards. Eather more than half of tlie shell — the anterioi^ 
part — is ornamented with thirteen narrow, sharp, radial ribs, which are separated 
by broad, flat, or slightly concave interspaces ; posterioi-h* these ribs become 
smaller and less widely separated ; on the middle part of the shell a few indistinct 
concentric ribs are seen. The posterior part of the shell is nearly smooth, and is 
separated from tlie ribbed area l)y a slight depression ; a cui'ved carina extends 
from the posterior side of tlie iiml)i) towards the postero-vciilral extremity. 

Affinities. — Only one specimen lias Ijeen seen; it resend)les closely M. seiui- 
costata (Agassiz^), but is rather shorter, and the posterior limit of the ribbed area 
is more sharply defined than in most examples of M. yciiiicoslnfa. Judging from 

1 'Etudes crit. Moll. Foss.,' Mves (1842), p. 51, pi. ii, figs. 1, 2, pi. iii', fig. 11. Pictet ami 
Campiche, 'Foss. Terr. Crct. Ste. Croix' (' Mati'r. Pal. Suisse,' ser. 4, 1865), p. 77. pi. cv, figs. 1, 2. 
Moescli, 'Mod. Phohulomveu ' (1874), p. 85, pi. xxx, fig. 4, i)l. xxxiii, figs. 3, 4. pi. xxxvi, fig. 1. 
Douvillr, ■ Bull. Soc. geol. de France,' ser. 4, vol. vii (1907), p. 112, pi. ii, fig. 8. Jloescli includes as 
a svnonvm PhoJadomya Trihohti, Pictet ami Caiiipiclie, op. cit., p. 8!l, \>\. cvi, fig. 8. Pictet and 
CanipicLe include P. Moreuna, Buviguier, ' Statist, gi'ol., etc., de la Meuse ' (1852). Atlas, p. 8. pi. viii, 
figs. 21. 22. 



254 CRETACEOUS LAMELLIBRANCHIA. 

the figures given by several authors, that species varies considerably, so that it 
seems probable that when more English specimens have been obtained it will be 
possible to refer them definitely to M. semicostata. 

Distribution. — Lower Greensand of Furze Hill, Faringdon. 



Genus — Gon'iomya, L. Ar/assi;:, 1842. 
(' Ktudes t-rit. Moll. Foss.," Mves, pp. xii, 1.) 

GoNioMYA Archiaci {Pictct and Eenevlrr), 1855. Plate XLII, figs. 4, 5. 

1855-6. Thracia Archiaci, F. J. Pidet and E. Beneiner. Foss. Terr. Aptieii 

(Matt'r. Pa,l. Suisse, ser. 1), p. 67, 
pi. vii, fii,'. 5. 
1858. - — Pidet and Renevier. Ibid., p. 176. 

1865. Pholadomya thracioides, F. J. Pidet and G. Campidie. Terr. Crut. Ste. 

Croix (Mater. Pal. Suisse, ser. 
4), p. 92 (Gohiomi/a). 
1870. GoNioMYA Archiaci, F. Stoliczka. Palseout. Iiidica, Cret. Fauua S. liidia, 

vol. iii, p. 75. 

Description. — Shell ol^long, convex, nearl}^ equilateral. Anterior margin 
rounded. Ventral margin slightly convex or nearly straight, ncai'ly parallel with 
the dorsal margin. Posterior margin truncated, oblique, slightly convex, forming 
a rounded angle with the ventral margin and an obtuse angle with the postero- 
dorsal margin. Umbones of moderate size, with a faint rounded carina extending 
postero-ventrally, above which the shell is compressed ; lunule and escutcheon 
elongate, depressed, limited by carina?. 

Ornamentation : Anteriorly to the umbones there is a ribbed area in which the 

ribs extend oblicjuely backwards ; posteriori}' to the umbones is another ribbed area 

in which the ribs are nearly perpendicular to the postero-dorsal margin, Ijut 

slightly curved ventrally. The anterior, ventral, and postero-dorsal parts of the 

shell are Avithout ribs, and show growth-lines only. Near the umbo the ril)s of 

the two areas are connected by horizontal ribs, but ventrally these horizontal ril)s 

are absent or indistinct. Some parts of the shell are marked by rows of small 

pits. 

Measurements : 

(1) (2) (3) 

Length . . 33 . 28 . 19 mm. 

Height . . 19 . IG . 11 „ 



'& 



(1 — 3) Crackers, Atherfield. 



GONIOMYA. 255 

Affinities.- — This species is less inequilateral, and the ri])s are less extensively 
developed than in (J. candata, Agassiz.^ 

Bemarks. — English examples of this species were identified by Pictet and 
Renevier, who state that the forms referred by Forbes- to Pholaclomya Agassizi 
are really specimens of G. Atrhiari. 

Type.— From the Aptian of the Perte-du-Rhone. 

DistrihuiicDi. — Lower Greensand (Crackers) of Atherfield.^ 

GoNiOMYA Mailleana {d'Orhi,ju)j), 18-1-5. Plate XLII, figs. 6, 7. 

1845. Pholadomta Mailleana, A. (TOrhiyny. Pal. Frauc. Terr. Cri't., vol. iii, 

p. 355, pi. ceclxiv, figs. 1, 2. 
1845. GoNioMYA Mailleana, L. Agassiz. Etudes, crit. Moll. Foss., Myes, p. xiv. 
1850. Pholadomia Mailleana, A. d'Orhigny. Prodr. de Pal., vol. ii, p. 157. 
1854. Pholadomta Mailleana, /. Morris. Cat. Brit. Foss., ed. 2, p. 220. 
1865. — —F.J. Pictet and G. Campiche. Terr. Crct. Ste. 

Ci'oix (Mater. Pal. Suisse, ser. 
4), p. 93 (Goniomya). 
? 1868. Pholadomya Mailleana, A. Briart and F. L. Cornet. Meule de Bracque- 

giiies (Mt'm. cour. et Mem. des 
Sav. ctraugers, vol. xxxiv), p. 83, 
pi. vi, fig. 12. 
1870. Goniomya Mailleana, F. Stoliczka. Palieont. ludiea, Cret. Fauua S. 

India, vol. iii, p. 75. 
? 1885. Pholadomya (Goniomya) Mailleana, F. NiitUng. Die Fauna d. baltisch. 

Cenomau. (Palteout. Abbandl., 
vol. ii), p. 36, pi. vi, fig. 9. 

Descripiiuii. — Shell elongate, sub(iuadrate, convex, very ine(juilateral. Anterior 
part not so high as the posterior part, compressed, with rounded margin. 
Antero-dorsal margin concave. Postcro-dorsal margin long, nearly straiglit, and 
nearly parallel to the slightly convex ventral margin. Posterior margin truncated, 
oblique, forming a rounded angle with the ventral margin, and an obtuse angle 
with the postero-dorsal margin. Umbones pointed, directed anteriorly. Lunide 
concave, elongate-ovate, limited by a carina. Escutcheon long, deep near the 
umbones, limited by a carina. Between the carina of the escutcheon and a 
rounded ridge extending from the umbo towards the postero-ventral margin the 
shell is concave. 

1 'Etudes crit. Moll. Foss.,' Myes (1842), p. 22, pi. ih, figs. 1—3, pi. i, fig. 1. Plwlndomya 
Agassizi, d'Orbigny, 'Pal. Franc. Terr. Cret.,' vol. iii, p. 352, pi. ccclxiii, figs. 1, 2; Pictet and 
C'ampielie, ' Foss. Terr. Cret. Ste. Croix ' ('Mater. Pal. Suisse,' ser. 4, 1865), p. 84, pi. cvi, figs. 4 — 6. 

2 ' Quart. Jouru. Geol. See.,' vol. i (1845), p. 239. Morris, ' Cat. Brit. Foss.,' ed. 2 (1854), p. 176. 
■' An imperfect specimen of Goniomya from the Tealby Limestone of Claxby is iu the Sedgwick 

Museum, Cambridge. 



256 CRETACEOUS LAMELLIBRAXCHIA. 

Ornamentation consists of rounded riljs ; those in front of tlic niabones are 
nearly straight and slope obliquely backwards and downwards ; those behind the 
umbones are curved and more or less nearly parallel to the posterior and postero- 
dorsal margins; near the ventral margin the ribs become more nearly concentric 
and are often less distinct (especially on the median part) than on tiie dorsal 
{lortion of the shell. 

AQinitiea. — This species differs from (j. ih'.-^iijnuta (Goldfuss)' in the smaller 
curvature of the ventral margin, and in the truncated form of the posterior 
margin. It is closely allied to (I . ciiusiijuiitu, Romer,- but the anterior curvature 
of the umbones is more marked. 

Remarks. — This species has been identified b}' comparison with a specimen 
given me by M. Raoul Fortin from the same locality as the type. 

Ttjpe. — From the Cenomanian of Mte. Ste. Catherine, Rouen. 

Disfrihnfion. — Upper Greensand (zone of Bfltlifnhachia roatrnta) of Blackdown, 
Devizes, and near Maiden Braillev. Base of Chalk Marl of Chard. ^ 



i^(u;i/Z//— PLEUROMYID.^, Z///e/. 

Genus — P;.EDR0MTA, L. Aijassiz, 1842. 
(' Etudes crit. Moll. Foss.,' Myes, p. 231.) 



Pleuromya Orbignian.v (Uoiiilliev), 1847. Plate XliTTI, figs. 1, 2 a — c. 

1847. PanoPjEa. Obbigniana, C. Rouillier. Bull. Soc. Imp. Nat. Moscou, vol. xx, 

p. 407; vol. xxi (184.8), p. 281, 
pi. G, fig. 24. 

JJescrijjf.ion. — Shell oval, convex, inequilateral, with a small posterior gape. 
Anterior and posterior margins rounded. Ventral margin considerably convex. 
Umbones moderately prominent, incurved. Shell depressed in front of and l)ehind 
the umbones. Surface nearly smooth, but ornamented with linear, radial ribs, 
which are sometimes parallel, sometimes irregular; in some places the ribs are 
replaced by rows of minute tubercles. 

Affinities. — The English specimens agree closely with examples from the Lower 

1 ' Petref. Genu.,' vol. ii (1840), p. 264, pi. cliv, fig. 13. Holzapfel, ' Mollusk. Aachen. Kreide ' 
(Palseoutographica, vol. xxxv, 1889), p. 153. 

■ 'Die Versteiu. d. nord-deutsfli. Kreidegeb.' (1841), p. 75, pi. x, fig. 3. Midler, 'Mollusk. 
Untersen. v. Braunschweig u. Ilsede' (1898), p. 71, pi. x, fig. 7. 

^ A small spcL'iniou of Goniunn/a has beeu found in the Chalk of Triiuiugham by Mr. R. M. 
Brydone. 



TJOPTRTHA. 257 

Volgian of Moscow, wliich were identified by Prof. Pavlow, l)ut their resemblance 
to Rouillier's fio-m-e is not quite so close. Some of the smaller specimens approach 
P. peregriaa (d'Orbigny'), which is said to differ from /'. Orbujmana by smaller 
curvature of the ventral margin, the presence of a shallow depression extending to 
the ventral margin below the umbones, and l)y the ornamentation consisting of 
radial rows of minute tubercles instead of linear ribs. One specimen from Spilsby, 
however, shows both types of ornamentation, suggesting that the two species are 
not really distinct. The hinge is not seen in any of the English specimens of /'. 
Orhirjniaiia, but the figure given liy Rouillier, although not fpiite satisfactory, is 
suggestive of I'miopea; the form of the shell, however, resembles that of some 
Jurassic species of Flenromiin. 

DistrilmtloiL. — Spilsby Sandstone (zone of Belemuitus laturalls) of Dounington. 



Famil I/— FOnOMYAGIDM, Dall. 
Qeniis — LiorisTHA, F. B. Meel; 1864. 

(' Check List Invert. Foss. N. America,' pp. 12, 32 ; T. A. Conrad in Kerr's ' Keport Geol. Survey 
N. Carolina,' vol. i, 187.5, Appendix A, p. 28 ; Meek, ' Invert. Cret. and Tert. Foss. U. Missouri,' 
1876, p. 227.) 

Section — PsiLOMYA, Meek, 187G. 
(Ibid., p. 229.) 



LiopiSTU.v (PsiLo.MY.\) g[G.\ntd:.v [Son-erhij), 1818. Plate XLIII, figs. ;5, 4; Plate 

XLIV, figs. 1, 2. 

1811. CoRBULA ?, /. Parkinson. Or;:,'anic Eemaius, vol. iii, p. 226. 

1818. — GiGANTEA, J. Sowerby. Miu. Couch., vol. iii, p. lo, pi. ccix, 

figs. 5—7. 
1850. Pholadomya — A. d'Orhiijnij. Prodr. de Pal., vol. ii, p. 157. 
1854. Thetis — J. Morris. Cat. Brit. Foss., ed. 2, p. 227. 

18(3.5. _ ? _ F. J. Pidet and G. Campiclie. Ten-. Crct. Ste. Croix 

(Matc'r. Pal. Suisse, ser. 4), pp. 199, 210. 
1870. POROMTA ^ — F. StoUczka. Palseout. Indica, Cret. Fauna S. India, 

vol. iii, p. 42. 
1882. LiOPiSTHA — P. de Loriol. Gault de Cosne, p. 45, pi. vi, figs. 1—5. 

1 Murchison, Verneuil, and Keyserling, 'Geol. de la Russie de I'Europe,' vol. ii (1845), p. 468, 
pi. xl, figs. 10—12. The hinge is figured by Zittel, ' Handbuch d. Paliiont.,' vol. ii, p. 125. fig. 179, 
and ' Gruudziige d. Paliiont.,' ed. 2 (1903), p. 330, fig. 732. 

34 



258 CRETACEOUS LAMELLIBRAKCHIA. 

Description. — Shell large, rather thick, oval, elongate, inflated, the posterior 
2iart compressed, very inequilateral. Anterior part very short, with rounded 
margin, but its dorsal part only slightly curved. Ventral margin forming a 
considerable curve. Posterior margin obliquely truncated, more or less rounded. 
Postero-dorsal margin nearly straight. Umbones large, prominent, pointed, 
iuroUed, and with a more or less considerable forward curvature. A rounded 
carina extends from the front of the umbones to the middle of the anterior margin 
and foi-ms the boundary' of a deeply excavated area in front of the umbones. 

Ornamentation consists of liroad, rounded, concentric ril)s on the dorsal part 
of the valves except on the anterior excavated area. In passing vcntrally these 
ribs become less prominent and are soon represented by concentric lines. Rather 
widely separated radial rows of minute tubercles are present and leave small pits 
when broken off. Near the umbo small radial ribs are present. 

Meastirements : 

(11 (2) (;i) 

Length . . 128 . 110 . 90 mm. 

Height . . 89 . 82 . 08 „ 

(1—3) Blackdown. 

Affinities. — This species resembles L. {Psilomya) .^iq-)erha (Stoliczka^), but 
differs in outline, in the concentric ribs being confined to the dorsal part of the 
shell, and in the less inflated form of the valves. 

liemarks. — In the small examples of this species the shell is relatively shorter 
and more nearly orbicular in outline and the concentric ribs cover the whole 
or nearly the Avhole of the valves. The radial ribs near the umbo are seen 
in only a few specimens. 

Ttjpe. — From Blackdown, in the British Museum. 

Distrihntioii. — Upper Greensand (zone of Srlila'ulxicliid rustrata) of Blackdown. 

LioPiSTiiA, sp. Plate XLIII, fig. 5*^' — r. 

Description. — Shell oval, slightly inequilateral, inflated, posterior part com- 
pressed, with a shallow furrow near the postero-dorsal margin, concave in front 
of the umbones. Anterior and posterior uuxrgins rounded; ventral margin 
considerably convex. Umbones prominent, curved inwards and forwards. 

Ornamentation consists of numerous (about twenty-nine), narrow radial ribs 
l)eai'ing small tubercles, and separated l)y concave interspaces of greater breath 
than the ribs. On the postero-dorsal part of the shell ribs are absent. The 
ribs are crossed by faintly marked concentric rings. 

Reinarldi. — The only exanq)le of this species which has been seen does not 
1 ' PalseoTit. Indica, Cret. Fauna S. India ' (1870), p. 4.S, pi. iii, figs. 2 — 4. 



CUSPID ARIA. 259 

show the hinge, but it is provisiouully referred to LiopistJia on account of its 
external resemblance to some species of that genus. ^ It should lie noted, how- 
ever, that it is also similar to some species which are believed to belong to the 
genus PJioladomi/a." 

Bisty'ihuflo)!. — Red Limestone of Hunstanton. 



i^'rt)«/Z//— CUSPID ARIID.E, DalL 

Genus — CaspiDAiMA, G. D. Nardo, 1840. 
(' Anu. Sci. Lombardo-Veueto,' vol. x, p. 49.) 



CuspiDAKiA SAiiAUDiANA (Firfcf find Camjnclie), 186-i. Plate XLIII, fig. 6o,h; 

Plate XLIV, fig. Sn,l. 

1864. NE^ffiiEA Sabaudiana, F. J. Pidet and G. Campiche. Foss. Terr. Cret. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), 
p. 40, pi. e, figs. 5 — 7. 

Descnptioii. — Shell inflated, oval, oblique, slightly inequivalve, anterior part 
sloping rapidly to the uiargin, posterior ])art compressed and produced into a 
pointed beak. Anterior margin rounded ; ventral margin convex, curving upwardsi, 
and passing gradually into the posterior margin. Umbones curved inwards and 
slightly backwards. A narrow postero-dorsal area is bent at an angle Avith the 
sides of the shell, and is limited by a carina. 

Ornamentation consists of strong, concentric ribs, most of which are con- 
tinued on to the posterior beak, where they become rather smaller and closer 
together ; on the sides of the ribs and in the furrows are ii few faint concentric 
lines. Length 14 mm.; height H mm. 

AMiiifies. — This species is more inflated, the anterior part is more rounded, 
and the concentric riljs are stronger than in C. jiitlchra (Sowerby). 

T]ipe. — From the Gault of the Perte-du-Rhone. 

Distnbntion. — Lower Gault of Folkestone. 

1 See, for example, Stoliczka, ' Crot. Fauna S. India,' vol. iii (1870), pi. ii, figs. 10, 11 ; Moesch, 
' Men. Pholadomyen ' (1874), pi. xxxv, fig. 5; Geinitz, 'Das Elbthalgeb. iu Sachseu ' (' Palaeonto- 
gi-aphica,' vol. XX, pt. 2, 1873), pi. xix, figs. 6,7; Wcller. 'Crct. Pal. New Jersey,' vol. iv (1907). 
pi. Iviii, figs. 3 — 9. 

- E.g. P. suhdmengig (d'Orbigny), 'Pal. Franc. Terr. Cret.,' vol. iii (1844), p. 38, jd. eel, figs. 
1—3, and ' Prodr. de Pal.,' vol. ii (1850), p. 1-57. 



2G0 CRETACEOUS LAMELLTBRANCHTA. 



Cuspin.vKiA u.\DU[,ATA {Sowerhi/), 1827. Plate XLIV, fig. 4. 

1827. NucuLA UNDULATA, J. df C. Soivefhi/. Min. Couch., vol. vi, p. 104, jil. dliv, 

fig- 3. 
1854. Ne^ra ? — J. Morris. Cat. Brit. Foss., eil. 2, p. 216. 

1866. — —F.J. Picfef and G. Campiche. Foss. Terr. Cret. Ste. 

Croix (Mater. Pal. Suisse, ser. 4), p. 421. 
1871. — — F. StoUckza. Palaeont. Indica, Cret. Fauna S. India, 

vol. iii, p. 322. 

Eemarlis. — A few .specimens resembling Sowerby's figure of G. utidulatd Lave 
been found. They appear to differ from G. SabaucUana only in tlie less oblique 
form of the shell and the more convex postero-ventral margin. More specimens 
are needed in order to determine whether G. SaJiandidna and G. iimJulata are reall}' 
distinct or only varieties of one species. 

Tijpe. — The type was preserved in pyrites, and came from Folkestone ; it was 
formerly in the British Museum, but has now perished. 

Distrihution. — Gault of Folkestone. 



CusPiDAEiA PULCHKA (Sowi'rhi/), 1850. Plate XLIV, figs. .5, 6. 

1850. Leda pulchra, J. de C. Soirerbij in F. Bixon. Geol. Sussex, p. 346 (p. 382, 

ed. 2), pi. xxviii, fig. 10. 
1864. — ? — J. Morris. Cat. Brit. Foss., ed. 2, p. 205. 
1897. CuspiDARiA CAUDATA, H. Woods. Quavt. Journ. Geol. Soc, vol. liii, p. 393, 

pi. xxviii, figs. 19, 20. 

Description. — Shell convex, with the posterior and antero-dorsal parts com- 
pressed ; sub-triangular, oblique, somewhat inequilateral, highest in front of the 
umbones. Dorsal margin nearly straight. Anterior margin slightly convex. 
Antero-ventral margin rounded. Ventral margin curving upwards and passing 
gradually into the posterior margin, which forms an acute angle with the postero- 
dorsal margin. Umbones pointed, curved inwards and slightly backwards. 
Ornamentation consists of regular, concentric ribs which become indistinct on the 
antero-dorsal and postero-dorsal parts. 

Measurements ; 

(1) (2) 

mm. 









(1) 


(2) 


Length 


. 




27 


22 


Height 


. 




19 


15 


Thickness 


. 




14 


11 




(1,2) Upper Chalk, 


Norwicli. 





palcxontoovapbical Socict\?, lOlO. 



A J\r O N O G R A P H 



OF THE 



CRETACEOUS LAMELLIBIUNCHIA 



ENGLAND 



BY 



HENRY WOODS, M.A. 

UNIVERSITY LKCTUUKU IN TALiKOZOOLOli Y, CAMURIUGE. 



VOL. IL PART VIL 

ixocERA:\rus. 

Pages 261—284; Plates XLV— L. 



LOX DON : 
PRINTED Foi; T]IE PA L.KUNTOG K A 1' H I C A L SOCIETY. 

Jaxi'auy, ion. 



PBINTEU BY ADLABD AND SON, LONDON AND DORKING. 



CUSPIDARIA. 261 

Affinities. — When describing- tlie Mollusca of the Chalk Rock in 1897 only an 
imperfect specimen of G. pidciiva was available for study, and 1 identified it with 
G. camiata (Nilsson). Two better specimens from Norwich have now been seen, 
and anew figure of Nilsson's type has been published I)y Hennig.' The English 
form^figured by Sowerby as I^i'da pulrJira — differs from the type of ('. cnndnta in the 
relatively greater height of the anterior ])ar( of the shell, the more nearly posterior 
position of the umbones, and in the posterior rostrum proceeding from the \o\d\ 
of the hinge-line instead of below it. < '. piilrlim approaches closely the specimen 
figured by Goldfuss" as G. caiuhitu, and it was chiefly on account of this resem- 
blance that I identified the English form with Nilsson's species. Stoliczka^ and 
Hennig, however, consider that Goklfuss' specimen is nut an example of ('. cauddta. 
If all the specimens figured by foreign writers as G. (-midala really belong to that 
species then it is obviously extremely variable and might well include G. jndchra. 
Without an oppoi'tunity of studying a series of foreign specimens and a larger 
number of English examples it seems, at present, preferable to regard G. puirJira 
as distinct from G. candata. None of the English specimens shows e^'idence of the 
existence of such a long posterior beak as is present in the type of G. Cdudafa. 

A specimen of Gii.^^iidaria from the Upper Greensand of Uevizes (Plate XLIV, 
fig. 7) resembles some specimens of G. judrlini and may be provisionally referred 
to that species. 

Ti/2>e. — The type, from the '• Chalk of Kent," cannot noAV be found. 

Dint ribul ion. — Chalk Rock of Cuckhamsley, Berkshire, and Henley Park. 
Up|)er Chalk (zone of L'dcniiiilclla niucru)iafa) of St. Giles' Gate and Horstead, 
near Norwich. 



1 'Kevis. Lamellibr. i Nilssou's Petrific. Suecana Format. Cret.' (1807), p. 62. pi. iii, fig. 28; 
EavE. ' Molliisk. i Daumarks Kridtafi. I. Lamellil.r.' (1902), p. (35 [133], pi. iv, fi-. 2t. 

- ' Petref. Germ.,' vol, ii (1840), p. 251, pi. cli, fij,'. 17. Compare also WoUymauu, • Seuoiis v. 
Bieweude' ('Jalirb. d. k, preuss. geol. Landesaust.,' fiir 1900), p. 23, fig. 5 ; Miiller, ' Mollusk. d. 
Uutersen. v. Braunscliweig u. lUcdc ' (1898), p. 77, pi. x, lii,'s. 10, 11 ; Wolleiiumii. • Fauna dvr Liiue- 
Imrg. Kreide' (1902). p. 80. 

^ ' Palaiout. Iiidica, Cret. Fauna S. India," vol. iii (1870), p. 41. 



35 



2(32 CRETACEOUS LA.M KLIJIJUAXCll I A. 

i'W7»////-l'EllNIi).E, Zlnd. 

(Coiithiiied frniii pngf 05.) 



(li'lillS — IxoCKItAMI'S, J. Snirrrlii/,^ ISIO. 

(J. Piirkiasou [ex Sowerbj MS. J, 'Traus. Gruol. Sac.,' sor. 1, vol. v, 1819, p. 55. J. Sowurby, 
'Traus. Liuu. Soc.,' vol. xiii, 1822, p. 455.) 



Inocebamiis NHoOD.MiK.Nfsis, iV Orhhjii ij , 1 8 iij. Pliite XIjV, fig.s. 1, 2. 

18-10. iNociiR.VMus NEoco.MiENSis, A. d' Orbi'jiii/. Pal. Fram;. Torr. Ci\''t., vol. ili, 

p. 50;3, pi. cccciii, figs. 1, 2. 
1850. — — ,rOrl,:,i,n/. Vi-odr. de Pal., vol. ii, p. 83. 

1854. — — J. Morris. C.it. Brit. Foss., eil. 2, p. 170. 

1855. — — G. Collect II. Moll. Fos-i. de ITouue, p. 107. 
1869. — — F.J.FidetaiulG.aunpiche. Foss. Terr. C ret. 

Ste. Croix (Mat.'r. Pal. 

Suisse, ser. 5), p. 104. 

1900. — — A. Wollem-.mn. Die Bivalv. u. Gastrop. d. 

deutscli. u. holljiud. 
Neocoms, p. (50. 
? 1905. — E. llu-hurt. Die Fauna d. SL-liauniliui-ix- 

Lippe'scheu Kreidemulde, 
p. 44, pi. ix, fiLjs. 4-6. 

Descrij.itluii. — Shell iueciuivalve, vei-y iiit'quiliiteral, a little liiu'lier than long. 
Valves convex, with flattened sides, and the postevior part uoiupre.'^.sed. Anterioi' 
margin iicnrly straiglit ; posterior and ventral margins rounded. Posterior 
margin Cdi'iiiing nii obtuse angle with the hinge-line. Anterior part nearly 
peri)enilicul;n' to the plane of the valves and excavateil near tlie nndjones. 
Und)ones terminal, eurved inwards and Forwards. Uinge-line eipial to mure tlian 
Indf the height of tlie sliell, and nia]<ing an angle of ahoiit l(H»' willi the anterior 
margin. 

Ornam'ntation con.sists of narrow, regular, coneenti'ie rilis witli an lui.sym- 
metrical eiirvature; the interspaces are I)road and regularly concave. 

' In roarran^'injj llic lullcrtiou of Iimeenuiii in tiir IJrilisli Muscuni, Mr. K. B. Newton and Mr. 
C. D. Sherboru have found several tvpe-speeinieus, (he existence of which liiid not been prcviuuslv 
reeo<rnised; this discovery has great Ij facilitated my work. I am also imlel)ted to Mr. Newt(Ui and 
Mr. Sherborn for assistance in selectiny specimens for fi^'uring. I wish to thanl; Jlr. 0. 1'. Chat win 
for infoniiatiiin respecting 1 lie zonal distribution of the sjioeies of Iiinrerniiiii.-< in (he Chalk and for 
other assistance Dr. Blackniore, Dr. Rowe, and Mr. G. E. Dildey have helped by the loan of 
numerous specimens from their collections. 



INOCERAMUS. 203 

Affinities. — Sec I. (nif/liciis (p. 201). 

/. iieocomtensis appears to be allied to ./. Kivuhli, Scliliiter,' of wliicli only one 
figure has yet been published. 'I'li(> differences seen are in the greater relative 
height, the more inequilateral form, and the greater convexity of the curve of the 
ribs of 1. ncocomiensis.^ 

Iieiii(ni'f<. — This species was first recorded in England by Fifton. Onlv a few 
specimens have been seen; they agree fairly well with d'Orbigny's figure, but the 
ribs appear to be better defined, and usually the posterior ear-like part is less 
distiiu-tly limited. The English specimens are not sufficient to show whether the 
inefpmlity of the valves is as great as in irOibigny's figure. 

7//y(''. — Prof. Boule informs me that d'Oibigny's figures are restorations based 
on two specimens from the Barreiuian of Bettancourt. The types are in the 
Natural History Museum, Paris. 

Disfrihiition. — Lower Greensand (Fitton's Bed 13) of Atherfield. ITythe l^eds 
of Lympne. Lower Greensand of Nutfield. 

IXOCEIIAMUS, Sp. 

A few specimens of Tnoceramvs, not sufficiently perfect for description, have 
been found in the Speeton Clay (zone of Belemnites Idfi'nili.s) and in the Spilsby 
Sandstone of Holton and Acre House. 



L\ocei;amus Salomoni, iVOrhifjny, 1850. Plate XLV, figs. 3 — 7. 

1850. Inoceramus Salomoni, A. d'Orhujny. Prodr.de Pal., vol. ii, p. 13!*. 
1853. — — F.J.PiddandW.Roux. Moll. Fo.ss. Gros vorts 

de Gfiu-ve, p. 5Ul, 
pi. xlii, fig. 3. 
1855. — — G. Coiteau. Moll. Foss. de rYonue, p. 107. 

1869. — — F. J. Pictet ami G. Campkhe. Terr. Crtt. Ste. 

Croix (Mater. Pal. Suisse, 
ser. 5), p. 109, pi. clx, figs. 
5—8. 

Defrrijjtioii. — Lcit valve inflated, subquadrate, very inequilateral. Length and 
height nearly equal. Anterior half of valve very convex ; posterior half compressed. 
Anterior end of valve more or less nc^arly perpendicular to the plane l)etween the 
valves, and concave near the umlio. I'mbo anterior, prominent, pointed, incurved. 

' See footuotc on p. 267. 

= Compare also forms des(ri))ed bv Schmidt as allied to /. ne<,coniit'ii>'is, 'Mi'm. Aead. Iiii].. Sei. 
St. Petersb.,' ser. 7, vol. xviii (lS72), pp. 155—161, pi. ii, fig. 8, pi. iii. figs. 6—9. 



264 CRETACEOUS LAMELLIBRANCHIA. 

A broad, usually shallow sulcus extends from l)elow the umbo to the ventral margin, 
where it produces a slight sinuosity ; usually the sulcus starts at some distance from 
the umbo, and may consequently l)e absent in small specimens. Ornamentation 
consists of small, narrow, somewhat irregular concentric ribs, separated by broad, 
shallow, concave interspaces. 

Affinities.- — This species is related to T. rnnccntrwus, Parkinson, but is dis- 
tinguished by its sul)quadrate outline, by the length and height being ueai'ly e(iual, 
and by the presence of the sulcus. 

liemarl's. — All the specimens seen are internal casts of left valves. The 
examples figured by Pictet and Roux and by Pictet and Campichc are also left 
valves. 

Tiipe. — D'Orbigny's specimens came from the Alljian of Novion, Clar, Geraudot, 
and Saint FJorentin. 

lihtriJint'um. — Miiiiuiullnfus bed of Copt l^oint, Folkestone. 



Inoceramus AXtiLR'us, sp. uov. Plate XLV, figs. 8 — 10. Text-tig. 2l,i. 

1822. Inoceramus, sp., G. Mantel!. Foss. S. Ddwus, ]i. S>6, jiI. xix, fig. 20. 
1859. — Crispii, T. Wiltshire. The Red Chalk of Englaucl (Geol. 

Assoc), p. 16, pi. i, fig. 4. 
1875. — coNCENTRicus, A. J. Jukes-Browne. Quart. Jouru. Geol. See, 

vol. .\.\xi, p. 299. 

T)escrij)lh>n. — Shell equivalve or nearly equi valve, very inequilateral. Anterior 
part of shell convex, the convexity decreasing with age ; posterior part com- 
pressed, flattened. Anterior slope of valves steep. Anterior margin moderately 
convex ; ventral margin very convex ; posterior margin curved, and forming an 
obtuse angle with the hinge-line. Length of hinge equal to rather more than a 
third of the height of the shell. IJmbones nearly terminal, with a small anterior 
curvature. 

Ornamentation consists of strong, regular, concentric ribs, which have a sub- 
sj'mmetrical curvature, and become less distinct on the posterior flattened part of 
the shell. The ril)s have rounded summits, and are separated by broad rounded 
furrows with symmetrical slopes. Some of the I'ibs bifurcate, some maybe dis- 
continuous, or new I'ibs may be intei'calated. 

Affinities. — The equal size of the valves, the greater convexity of the curve of 
the ril)s, the convex form of the anterior margin, and the outward slope of the 
anterior part of the valves distinguish this species froai 7. neocomieiisis, d'Orbigny 
(p. 2(i2). 



INOCERAMUS. 



265 



I. amilicus also resembles /. Ewaldl, Scliliiter,' l)iit is ivliitively lii.ulici-, iiinrc 
inequilateral, and the ribs are more strongly curved. 

li'riiiarJcs. — This species has been usually ideutified as /. (■(Diceiifricns, I'arkinsun, 
but the equal size of the valves and other characters readily distinguish it from 




,-<*<"' 



Fig. 29. — Inoceramus angliais, sp. nov. Red Limestone, Hunstanton. Sedgwick Museum, 
Cambridge. Part of right valve. Natural size. 

that species. An example from Hunstanton was figureil l)y Wiltshire as /. CrUpii 
(= Crippsi), Mantell. 

Distribution. — Red Limestone of Hunstanton. Gault of Folkestone. Cam- 
bridge Greensand (derived from the Gault). Marl in the Gault of Roydon, West 
Norfolk. Upper Greensand of Haldon, the Isle of Wight, and Devizes. 



liNouiiKAMUs coxciiNTiucus, Pd rlcinxitii, 181'.l. Plate XLV, fig. 11; Plate XLVI, 

figs. 1 — 10 ; Plate XLVII, figs. 1, 2. 

1819. iNOCERAMtrs coNCENTRicus, J. ParJii iinon . Trans. Geo!. Soc, ser. 1, vol. v, 

p. 68, 1)1. i, &g. 4. 

1821. — — J. Sowerhij. Miu. Couch., vol. iii, p. 183, pi. 

cccv, figs. 1 — 6. 

1822. — — G. Manlell. Foss. S. Downs, p. 95. pi. xix, 

fi-s. 15, 19. 
— — — A. Broiignlart in Curler. Ossemens Foss., 

vol. ii, pt. 2, pp. 333, 33(5. 
609, pi. vi. fij,'. 11. 
1828. — ORTPH.«:oiDES, J. de C. Sowerby. Jliu. Coneb , vol. vi, p. 161, 

pi. illwxiv. fijx. 1. 



1 See footnoU' on p. 267. 



266 CRETACEOUS LAMELIJBEANCHIA. 

1833. Catili.i's ptkiformir, H. Muhclin. Ma<,'asin do Z<i()]ni;i(\ iii, Classo 5, pi. 

xxxii. 
183C. Inocekamu.s concentricus, A. GoIiI/hsk. Petref. Gonii., vdl. ii, p. Ill, 

pi. cix, fi<;s. 8'/, b, c, (uon 
8d, e,f). 
? 1842. — — P. M,tt](n-(,n. Catal. Foss. des Bouches-du- 

Rlionc, p 173. 
184C. — A. iVOrhujnij. Tal. Franc. Terr. Crct., vol. iii, 

p. 50fi, pi. cccciv. 

— -- — ^t. Lci/iiicfii'. Statist, geol et niiii. do rAube, 

Atlas, pi. V, fi'^. 12. 
1850. — -- H.B.Geinitx. Das Quadorsandst. oder Kreide- 

j;ol). ill Dontsclilund, p. 174. 

— — ~ A. iVOrhUjny Prodr. de Pal., vol. ii, p. 138. 
18.53. — — F. J. Piclet ami W. Eoux. Moll. Foss. Gros 

verts de Geneve, p. 500, 
pi. xlii, &g. 2. 

1854. — -- J.Morris. Cat. Brit. Foss., cd. 2. p. ItSP. 

— — ORYPH^EOiDES, /. Jl/oms. Ibid., p. 169. 

1855. — CONCENTEICTTS, G. Cottcau. Moll. Foss. de I'Toune, p. 1(»7. 
186<). — — F. J. Piciet ,1,1,1 G. Cminchc. Terr. Cn't. Ste. 

Croix (Mator. Pal. Suisse, 
ser. 5), p. 107. 

1876. — — J. F.Whiteiivrs. Mesozoic Fossils (Geol. Surv. 

Canada), vol. i, pp. 79, 241. 

1877. -■ — C. Schliifer. PalfEoutographii-a, vol. xxiv, p. 

255. 

— — — G. Bi'ilim. Zoitsehr. d. deutscli. Lfool. Gesellscli., 

vol. xxix, p. 238. 
1897. — It. B. Newton. Proe. Dorset Nat. Hist, and 

Antiq. Field Club, vol. xviii, 
p. 88, pi. iii, fig. 12. 
1906. — A. Wollenvmn. Jalirb. d. k. preuss. geol. 

Laudesaust. fiir 1906, vol. 
xxvii, p. 271. 

Non 1837. — — G. Fischer de Waldheim. Orvctogr. de Mos- 

cou, p. 177, pi. XX, figs. 1 — 3. 
(= Aucella Keyserlitigiana, 
Trautschold). 

— Ibl41. — — F. A. Iti'micr. Die Verstein d. uord-doutsoli. 

Kroidegeb., p. 61. 
-— 1845. — - E. Forbes. Quart. Journ. Geol. Soc, vol. i, 

p. 247 (/. iii'ocomii-ii)!i.>\ d"Orb.) 

— 1846. — — ■ A. E. Reuss. Die Verstein. der iiilhni. Kroide- 

forniat., pt. 2, p. 24 

— 1847. — — J. Midler. Pelref. der Aaolion. Kroidef.. pi. 1, 

p. 30. 



INOCERAMUS. 2G7 

Noil 1875. Inoceeamus concentricus, A. J. Jukes-Browne. Quart, Jouni. Gcol. Soc, 

vol. xx.\i, p. 21)9. 

Desciiplinii. — Slicll iniiiv or less ovaic, much liii^-licr tliaii long, vei'v iii('(|iii- 
lateral and ineqnivalve. Anterior part of valves flattened or concave, often more 
or less nearly perpendicular to the plane between the valves. Posterior part of 
the valves somewhat expanded and less convex than the part below the uml)ones. 
Postero-dorsal part forming a small wing. Left valve very convex, Avith a high, 
nai'ruw, pointed, terminal uniljo which is considerably incurved and bends forwards. 
Right valve considerably less convex than the left valve, with a small, terminal 
umbo curved forwards but only slightly inwards. Hinge-line less than half the 
height of the shell. 

When the shell is perfect the surface is nearly smooth except for nuTuerous 
ivgular growth-rings. When the outer layer of the shell is wanting concentric 
undulations or ribs having an unsymmetrical curvature are seen, and are separated 
by concave furrows. 

Affinities. — /. concctifriciM has been compared l)y Wolleniaun with 7. Val-oIiH, 
Schli'iter,^ but the prominent umbo and other characters readily distinguish it from 
that species. See also I. cuncentricus var. snbsHlcatuf, and I. snlcatn.<! (below). 

liemarJcs. — Whilst the left valve in the specimens from the Blackdown Greensand 
agrees closel}- with that of specimens found in the Gault, the right valve in many 
(but not all) cases is relatively moi-e convex, especially between the umbo and the 
postero-veiitral extremity, and the ribs are more sharply cui'ved. A similar 
modification is seen in the examples from the Red Limestone of Hunstanton. 'J'liere 
seems no reason for regarding the specimens with these characters as forming 
more than a local variety dependent on the fact that they lived muler conditions 
different from those Avliich prevailed where the Gault was deposited. 

/. r/ri/plicCuichs, Sowerby, was founded on an internal cast of /. i-oiirnitrirns 
from the Upper Greensand ; in such casts the ribs are more prominent than on 
the surface of the shell itself. 

All the examples from the Candjridge Greensand which have been recorded as 
I. coiiccnfricKs ai)j)ear to l)elong to 1. aiir/licii-s (p. 2(1 1). 

Tijpes. — The type, which came from the Gaidt of Folkestone, cannot now be 
found. The specimens from the same locality figured by Sowerby and by ]\hintel!, 
and the type of /. ijnjphxo'ules from the Upper Greensand near hyiiu' Rt-'gis, are in 
the Hiitish ^luseum. 

Didiiliatinii. — In all zones of the (iault of Folkestone. (!ault of Aylesford, 

1 'Mouatsber. d. k. piviiss. Aka.l. Wissenscli., Birliu' (18(30), p. 345. Schlutor, ' Piiliuonto- 
iji-.ipliicii,' vol. .\xiv (1877;, p. 255. Wollomaim, *• Bivalv. u. Gastiop. J. iiorddeutSL-h. Gaults" 
(' Jaliil). d. K. prciiss. geol. Laudesaust.,' vol. .\.\vii, 1900), p. 272, pi. vi, fig. 9. 



2G8 CRETACEOUS LAMELLIBRANCHIA. 

Dunton Green (Kent), Black Yen, and Okeford Fitzpaine. Upper Greenland 
(zone of Schlcenhachia rosirata) o^ Blackdown, Sidmoutli, Lyme Regis, and Potterne 
near Devizes. Limestone in tlie Gault of AVe.st Bilney, Roydon, and Grimston 
(West Norfolk). Red Limestone of Hunstanton. 

Inoce1!.\mu.s coNCKNTiiicrs var. sriiSLTi.f'ATi'S, WilUhiri', 1869. Plate XfiVII, figs. 

3—14. 

1853. Inoceeamus svt.cA-rvs, F. J. Pictcf and W. Ronx. Mull. Fos.s. Grcs verts 

de Geneve, p. 499, pi. 
xlii, figs. 1 d, e, /. 

1869. — svbsvIjCatvs, T. Wllfyh ire. Quart. Jouru. Geol. Soc., vol. xxv, 

pp. 188. 190. 

1879. — — F. Cf. H. Pm-r. 'Ihe Gault, p. 54. 

In the lowe.st zone of the U])per (iuult there occur tornis of Lioccrainns which 
differ from I. concentricus only in the fact that radial plications are more or less 
extensively developed. Li these forms every stage can l)e traced l)etween /. con- 
centricus without plications into forms in which the plications are almost as 
complete as in /. snlrnfiis. A specimen, which differs from I. concent ricns only in 
the occurrence of one shallow plication, is shown in fig. 3 (Plate XLVII) ; others 
are similar, hut jiossess two or three plications (Plate XLVII, figs. 4, 5). In most 
cases the early ])art of the shell agrees entireh' Avith I. concentricus ; but the 
duration of this stage varies considerably in different individuals, and sooner or 
later either a few or many plications are developed. When the plications are 
numerous and start from near the umbo the shell closely resembles I. sulcntnx, 
but may usually be distinguished by the rounded (instead of angular) form of 
the plications, and by the presence of concenti'ic ribs. For these forms, which 
characterise a definite horizon in the Gault, it will be convenient to adojjt as a 
varietal designation the name suhsnlcatns, given by Wiltshire in 18(59. 

From a study of many forms of this A'ariety it seems evident that /. snlmtus 
lias been derived from /. concrntricns by the grailual di'velopment of plications, and 
this view is in accordance with stratigraphical distribution, since /. concent ri ens is 
the earlier of the two species, being found throughout the Gault, whilst 7. snJcatns 
occurs in the upper })art of the Gault only. 

If 7. snlcatns has been dei'ived from I. coiicentricn.s, then it is clearly more 

nearly related to that than to any other species of Inoceramus, and cannot therefore 

1)0 placed in a separate genus or suli-genus [Aetinoeennnnx), as was proposed by 

Meek.' l"'urthef, in the early stages of the \i\v\vty sn1>snlcatns the shell is a typical 

1 ' Clieek List Ciet. Foss. N. Amer.' (' Suiitliscu. Miscell. Coll.,' No. 17", 1864), p. 32. Stoliezka, 
' Cret. Fauna S. India,' vol. iii (1871), p. 393. Meek and Haydeu, ' Invert. Cret. Tert. Foss. U. 
Missouri' (1876), p. 39. 



INOCERAMUS. 209 

l-iioceramnx, l)iit subsequently it possesses the chai'actcrs of Arlinorerniinis. Also 
it appears that a somc^Yllat similar plication has originated independently in I. 
Salumoni (p. 263), and probably too in 1. radians, Schli'itei',' and 1. fascial as, Miiller." 

Pictet and Roux I'egarded snhKuIcatiis as a variety of /. milratus in ■which the 
number of plications had decreased ; the stratigraphical distriljution and also the 
evidence of the extensive series of specimens of .suhsiilcahis which has now been 
obtained are opposed to this view. 

Distrihittioii. — Lowest zone of the Upi)er Gault of Folkestone. Upper Green- 
sand of Blackdown. Red Limestone of Hunstanton. 

Inocekamds sulcatus, rarliusou, 1819. Plate XLVII, figs. 15—20. 

1819. Inocekamus svj^catvs, J. Parkinson. Trans. Geol. Soc.ser. 1, vol. v, p. .50, 

pi. i, fit;;. 5. 

1821. — — J. Sowcrliij. Mill. Conch., vol. iii. p. 184, ])1. ccevi, 

figs. 1 — 7. 

1822. — — G. Matitell. Foss. S. Dowus, p. 95, pi. xi.x, fig. 16. 
— — — A. Brotiijniart in Citvier. Osscinens Foss., vol. ii, 

pt. ii, j.p. 333, 336, pi. vi, fig. 12. 

1836. — —A. Gohlfms. Petruf. Gonn., vol. ii, p. 112, ].l. ex, 

fig. 1. 

1837. — — W. Hi.<iii</rf. Lethsea Suecica, p. 56, pi. xvii, fig. 9. 
1846. — A. (VOrhiijrnj. Pal. Fianr. TeiT. Cret., vol. iii, p. 504, 

[.l. ccctiii, figs. 3 — 5. 
1850. — — A.frOrhlijtiij. Pimlr. de Pal., vol. ii, p. 139. 

1853. — — F. J. Piclet and W. liuiLi: Moll. Foss. Grcs verts dc 

Geneve, p. 499, pi. xlii, 
figs. li(-c (not d-f). 

1854. — —J. Morrie. Cat. Brit. Foss., e.l. 2, p. 170. 

1855. — — G. Cotleati. Moll. Foss. de I'Yonne, p. 107. 

1864. AcTiNOCERAMUs scLCATUs, F. IS. Meek. Check List Ciet. Foss. N. Amer. 

(Smithson. Miscell. Coll., No. 
177), p. 32. 
1869. Inocekamus stjlcattjs, F. J. Ficlet and G. Campiche. Foss. Terr. Cri't. 

Ste. Croix (Mater. Pal. Suisse, 
ser. 5), p. 105. 
1875. — — A. J. Jiikcs-Broune. Quart. Jomu. Geol. Soc., vol. 

xxxi, p. 298. 

1877. — C. Schliiler. Pala?ontogTapLiea, vol. xxiv, j). 266. 

1884. (AcTJNOCEBAMUs) SULCATUS, J. F. Whilcaiif. Mcsozoic 

Fossils, vol. i (Geol. Siirv. 
Canada), p. 241, pi. xxxii, 
fig. 3. 



1 ' Palttontographica,' vol. xxiv (1877), \>. 270. pi. iii, fig. 2. 

2 ' Jahrb d k i.rcuss. gcol. Landesansf. ffir' 1887 (1888), p. 416. pi. xviii, fig. 3. 

30 



270 



CRETACEOUS LAMELLIBRANCHTA. 



I'JOG. Inoceramus sulcatus, ^4. WoUcmann. Jahrlj. J. k. pruuss. geol. Landesanst. 

fiir 1906, vol. xxvii, p. 273, pi. vi, 
%. 10. 



Noil 1827. 



S. Nilsson. Petrif. Suecana, p. 18. 



Dcscrlpliou. — Shell more or le.ss ovate, mucli liiglier than long, very inequi- 
lateral, more or less considerably inequivalve. Anterior j^art of valves flattened 





Fia. 30. — Inoceramus, s^. Gault, Folkestone. Sedgwick Museum, Cambridye. Internal ciist nf liylit 

valve. X ^. 

or concave. Posterior part somewhat expanded and loss convex than the part 
below the umbones. Left valve very convex, with a liigh, narrow, pointed 
anterior umbo which is considerably incurved and bends forwards. Right valve 
rather less convex than the left valve, with a smaller umbo whicli bends forwards 
and slightly inwards. 

Ornamentation consists of strong angular radial ridges ([)lications), usually 
from eight to ten on each valve, which are often unequal in size and are separated 



mOCERAMUS. 271 

liy deep furrows. The ridges are often at unequal distances from one another; 
some of them start from the umbo, others may be intercalated or may arise by 
bifurcation. Fine concentric lines cover the shell and are folded where they 
cross the ridges and furrows. 

Affinities. — Although the radial plications give a distinctive appearance to this 
species, yet the form of the shell closely resembles that of I. concentvicuH, the main 
difference being that in the former the difference in the convexity of the two valves 
is usually less marked than in the latter. 

Types. — The type, from the Gault of Folkestone, is in the British Museum. 
The specimens from near Lewes, Folkestone (except figs. 1 and 2), and Clophill 
figured by Sowerby, and the specimens figured by Mautell are in the British 
Museum. 

.Distribution. — Gault of Folkestone, Aylesford, Ringmer, Eastbourne, the Isle 
of Wight, and Leighton Buzzard. Upper Greensand (zone of Schlcenbuchia 
riistrai(i) of Blackdown, Sidmouth, Black Yen, and Lulworth. Red Limestone of 
Hunstanton, South Willingliam (Lincolnshire), and Speeton. 

Inoceramus, sp. Text-fig. 30. 

Specimens of a large, slightly convex Inoceramus are found in the Gault 
of Folkestone and the Upper Greensand of Potterne (Devizes) and the Isle 
of Wight, but are not sufiiciently perfect for determination. The umbones are 
terminal, and the hinge-line is nearly at right angles to the anterior margin. The 
anterior parts of the valves slope steeply to the margin. Small and rather 
distant concentric ribs are present. This form shows some resemblance to I. jj/V7«,s 
(p. 279), but is less convex, and possesses fewer ribs. 

Inoceeamus tenuis, Mavtcll, 1822. Plate XLVIII, fig. J. Text-figs. 31, 32. 

1822. Inoceramus tenuis, G. Manfell. Foss. S. Downs, p. 132. 
1854. — —J. Morris. Cat. Brit. Foss., ed. 2, p. 170. 

? 1859. — — r. Wiltshire. Eed Chalk of England (Geol. Assoc), 

p. 16, pi. i, fig. 5. 
186(5. Peena lissa, II. G. Seeley. Auu. Mag. Nat. Hist., ser. 3, vol. xvii, p. 178. 

Non 1841. Inoceramus tenuis? F. A. Enmer. Pie Verstein. d. nord-dcntscli. 

Kreidegeb., p. 62, pi. viii, 
fig. 11. 

De.srr?/)//o/(.— Shell inequivalvo, very inerpiilateral, convex ; postero-dorsal 
part compressed ; antero-dorsal pait excavated and more or less nearly perpen- 



272 



CRETACEOUS LAMELLIBRANCHIA. 



diculai- to tlie plane of the valves; height greater than length. Hinge-line equal 
to a])out two-thirds of the height of the shell. Ventral margin very convex; 
posterior margin forming an obtuse angle with the hinge-line. Umbones terminal, 
curved inwards and forwards, the left umbo larger and more prominent than the 
right. Surface smooth, except for growth-rings. 

Affinities. — /. tennis resembles 7. roncentricus, but the left umbo is less 





Fio. SI.— Inocerumns tenuis, Mantcll. Chalk Marl, Hamsey. Tlio typo. No. 5SUU, BrUisli iMiiscum (Nat. 
Hist.). The specimen is sumewliat c-niiipiessod from front to back. Left valve and anterior view of both 
valves. Kiijht valve shown in the next fiijure. 



prominent, the length of the shell is relatively greater, and tlie concentric rings 
are less prominent. 

The fragmentary specimens described by Seeley as I'mtu lisaa a[)pear to belong 
to this species.' 

Ti/i,cs.—Jn the Britisli Museum (No. 589(») from the Chalk .Marl of Hamsey. 
A fragment, from the Red Limestone of Hunstanton, which appears to l)e one of 

^ Tlie form from tlie Kcd Limestone of Hunstaiiton wLieli wa.s named Fcniii Ininnrffsa bv Seeley 
is at present known only liy an imjiorfeel left valve. It is perhaps allied to /. (ftmis, but is remark- 
able in beiny mueli lonijei' than IiIl;!). The ty|ie is m the Sedgwick Mu.seiiiii, Canibriilge. Seeley, 
'Auu. Mag. Nat. Hist.,' .ser. ,!, vol. .wii (Ib'OG), p. 1711. 



INOCERAMUS. 



273 



the specimens on which Soeley's dosciMption of Pcnni Ussk was l)fise(l, is in the 



Sedgwick Museum, Canibridgc 




V 




Fio. 32. — Iiioceramws fi'n » is, Mantell. Rij4;lit valve. See Fig. 31. 

D'islrlhntion. — Red Limestone of Hunstanton, Loutli, and Speeton. 
Greensand of Ventnor and Pottei-iu'. f'lialk ^rui-l of llaniscv. 



Upper 



Inooeramus- Crippsi, Mantell, 1822. Plate X 1;V1 1 1, tigs. 2, :5. Text-figs. 33—35. 



1822. Inoceramus Cbipsii, G. Mantell. Fo.ss. S. Dowus, p. 133, pi. xxvii, dg. 11. 
1836. — LATUs, A. Gohlfuss. IVtref. trfriu., vol. ii, p. 117, pi. cxii, 

fig. 5 (non Mantell). 
1846. —A. d'Orhujivj. P.il. Franc. T.rr. Crot., vol. iii, p. 513, 

pi. ccccviii, figs. 1, 2. 
18.54. - Crisi'ii, J. Morris. Cat. Brit. Foss.. ed. 2, p. 169. 

190t. — LATUS, E. T. Neirtoii an I A. J. JiiJceg-Broime. In Jukes- 

Browue,Cret. Eocks of Britain, 
vol. iii, p. 449. 
1909; CitiPi'sr, J. fiiihm. Subhercyn. KreiJemuldi.- (Abhamll. d. k. 

prou.ss. <;eol. LauJosanst.. n.f., 5t>), 
p. 41, 1)1. ix, fig. 1. 



274 CRETACEOUS LAMELLIBRANCHIA. 

Non 1822. Inoceeamtjs latus, G.ManlfU. Foss S. Downs, ]>. 21G, pi. xxvii, fig. 10. 

— 1828. — — /. de C. Sowerhj. Min. Couch., vol. vi, p. 159, pi. 

dl.xxxii, fig. 1. 

— 1836. - Ciuspii,^.Go7((A'»«. Petref. Gfim.vol. ii,p. 116,pl.cxii,fig.4. 

— 1840. — — H. B. Geiiiitz. Char. d. Scliicht. u. Petref. des siichs. 

Kreidfgob., pt. 1, p. 27. 
1841. — i-xTva, F. A. Eomer. Die Versk'in. d. uord-deutsch. Kreidegeb., 

p. 61. 

— — — Cripsii, RiJmer. Ibid., p. 03. 

— 1846. — — H. B. Gfiiiilz. Gruudr. d. Versteiu., p. 464. 

— — — LATUS, Geinilz. Ibid., p. 463. 

— — — — A. E. Reiiss. Die Versteiu. der bohin. Kreidei'onuat., 

pt. 2, p. 25. 

— — — C EiPSii, Ite(s«. Ibid., p. 25, pi. xxxvii, figs. 10, 12. 

— 1847. — — J. Midler. Pelref. der Aachen. Kreidef., pt. 1, p. 30. 

— 1852. — — F. Romer. Kreidebild. v. Texas, p. 56, pi. vii, fig. 2. 

— — — LATus, Riiitier. Ibid., p. 60. 

— 1859. — CRispn,T. Wiltshire. Eed Chalk of England (Geol. Assoc.), 

p. 16, pi. i, fig. 4. 

— 1863. — Crifsi, A. V. St loiiiberJi. Zeitschr. d.deutscb. geol. Gesellsch., 

vol. XV, p. 152. 

— 1866. — — K. A. ZilteJ. Bivalv. d. Gosaiigeb.,ii(Denkschr. d. k. 

Akad. Wissensch , Wien, Math.-iiat. 
Ci., vol. xxv), p. 95, pi. xiv, figs. 1 — 5, 
pi. XV, figs. 1 — 5. 

— — — LATUS, Zittel. Ibid., p. 100, pi. xiii, fig. 7. 

— 1869. — CniFni, E. Favre. Moll. Foss. de la Craie de Lemberg, p. 132. 

— 1870. — i^ATVS, F. Rlimer. Geol. Oberschles., p. 316, i)l. xxxiv, fig. 12. 

— — — Cripsii, Rlimer. Ibid., p. 356, pi. xxxix, fig. 9. 

— 1871. — CuispiANUs, F. Stoliczka. Palaeont. ludica, Cret. Fauna 

S. India, p. 405, pi. xxvii, figs. 
1 — 3, pi. xxviii, fig. 2 (not pi. 
xxvii, fig. 3, 1. Heherti, Fallot). 

— 1872. — Cripsi, H. B. Geliiih. Das Elbthalgeb. in Sachsen (Pal- 

seontographica, vol. xx, pt. 2), 
p. 49, pi. xiii, figs. 11-15. 

— — — LATUS, Geinitz. Ibid., p. 45, pi. xiii, figs. 4, 5. 

— 1873. — — Geinitz. Neues Jahrb. fiir Miii., etc., p. 11. 
— • — — Cripsi, Geinitz. Ibid., p. 16. 

— 1875. — LATUS, C. Di'cocq. Assoc. Fran^. Avane. Sci. (Lille), p. 369. 

— 1876. — Critsii, D. Branns. Zeitschr. f. d. gesammt. Naturwissensch., 

vol. xlvi, p. 378. 

— — — ^ ? var. Bababini, F. B. Meek. Invert. Cret. Tert. 

Foss. U. Missouri, p. 49, pi. xii, fig. 3, pi. xiii, fig. 1 . 

— • — — — ? var. subundatus, J*. 2?. Jl/ee.'.-. Bull. U.S. Geol. and 

Geogr. Surv. 'J'erritories, vol. ii, p. 358, pi. iii, 
figs. 1, 3. 



— 1882. — 

— 1885. _ 



INOCERAMUS. o-- 

Nou 1877. iNOCEE.vMus Cripsii, C. Srhlnter. Pala^ontographica, vol. xxiv, p. 277 

18/8. _ I.ATUS, C. Ban-ois. Ann. Soc. gcol. Nord, vol. 'v, pp. 407, 

475. 

— 1879. — Ckipsii, vars. pboximus, suciensis, Bakabini, /. F. Wkiteaves. 

Mesozoic Foss., vol. i (Geol. Surv. 
CaiKula), j.p. 172—174. 
— H. Schroder. Zeitschr. d. doutsch. geol. Gesellscli., 
vol. xxxiv, p. 273. 
Ceipsi, E. Fallot. Ann. Sci. gool., vol. xviii, p. 250. 

- 1887. - CuiPsii, A. Peron. Hist. I'err. Craie S.E. du B.issin Anglo- 

Parisien, p. 158. 
~ ^^^^- ~ — G. Mnller. Jahrb. d. k. preuss. geol. Laudesaust. fur 

1887, p. 416. 
1889. — ~ E. Holzapfel. Die Mollusk. Aachen. Kreide (Palseon- 

togniphica, vol. xxxv), p. 222. 
~ ~ "" Gmvsi, A. Fritsch. Stud, i.u Gehiete der bOliin. Kreide- 

format., iv, Teplitz. Schicht., p. 82, fig. 73. 
~ ~ ~ ~ 0. Grlepenkerl. Seuon. v. Kouigslutter (Piil»ont. 

Abbaudl., Vol. iv), p. 50. 

— 1891. — Cripsii, /. Bohm. Palaeontographica, vol. xxxviii, p. 81. 
1892. — ~ K. FnUerer. Ober. Kreidebild. St. Croce (Palaiont. 

Abhandl., vol. vi), p. 80. 
~ ~ ~ Ckipsi, E. Stol/ey. Kreide Schleswig-Folsteius (ilittheil. 

Min. Instit. Universit. Kiel, vol. i), 
p. 241. 

— 1894. — Ckippsi, B. Lundgreii. Mammilatus och Mucrouatu zouema 

(K. Svenska Vet.-Akad. Hindi., 
N.F., vol. xxvi, No. 6), p. 45. 

— 1897. — Cripsii, R. Leonhard. Pateoutographica, vol. xliv, p. 49. 

— — LATUS, Leonhard. Ibid., p. 49. 

— 1898. — Ciirp.iii, G. iHnier. Mollusk. Uuterseu. v. Braunschweig u. 

Ilsede (Abhandl. d. k. preuss. geol. 
Landesanst., n.f., 25), p. 45, fig. 12. 

— 1899. — — Q_de Alessandri. Palaeont. Ital., vol. iv, p. 194, pi. 

xvi, fig. 9. 

— — — LATUS, Alessandri. Ibid., p. 196. 

— 1900. — Cripsi, a. Wollemann. Jahrb. d. k. preuss. geol. Landesanst. 

fiir 1900, vol. xxi, p. 18. 

— 1901. — LATVs, F. Sturm. Ibid., vol. xxi, p. 93, pi. x. fig. 2. 

— Ceipsi, H. Imkeller. Palaeontographica, vol. xlviii, p. 33. 

— 1902. — _ var. eadiosa, A. Qitaas. Ibid., vol. x.\x, 2. p. 170. 

pi. XX, figs. 9, 10. 

— — -4- Wollemann. Luneburg. Kreide (Abhandl. d. k. 

preuss. geol. Laudesaust., n.f., 
37), p. 72. 

— 1903. — LjLivs.W.Petratcheck. Jahrb. d. k. fc. geol. Rvi.hsanst., vol. iiii, 

p. 165. 



276 



CliETACEOUS LAMELLIBKANCHIA. 



Noil 11105. Inockramus Cripsi, T. Weyuer. Zoiisclir. J. Joutscli. geul. Gesellscli., 

vol. Ivii, p. 161. 

— 1906. — Crispianus, /. PelhiJ. Palseontograpliicii, vol. lii, j). l'32. 

— 1908. — Cripsii, a. StojaiKiff. Ann. gi'ol. min. Russie, vol. x, p. 121. 

Descr'ipiio)!. — Shell thin, (Miuivalve, inodenitely inequilateral, convex between 
the umbo and the vential margin ; postcro-dorsal part compressed and flattened ; 
antcro-dorsal marginal part ncaih' jieijicndicular to the plane of the valves and 

Fig. 33. 




Fio .34. 




Fia.33.— J«oferami(s Cripyii^i. Maiitfll. Tlic tyiu^, Biitisl. Mu.seum (Nat. Hist.) No. o8y3. Chalk Marl, 
Oft'hnin. IntiTiinl cast. Natural size. .... 

Fio. -i-l.—Inocerarnvs Crippsi, Mantoll. Clialk Marl. Internal cast of a left valve similar to the type. 
British Museum (Nat. Hist.) No. 589.5. Natural size. 

nearly straight. Ventral margin convex ; posterior margin only slightly convex, 
aiul forming more than a right angle with the hinge-line. Hinge-line forms an 
angle of about 1 10" with the antero-dorsal margin. Umboncs inconspicuous, 
pointed, not curved, at about a third of the length of the hinge from the anterior 
end ; in front of the umbones is a small, obtusely triangular ear. 

Ornamentation consists of broad, rounded, rather iiii'gnlar concentric ribs, 
which are strong anteriorly, and liecoine weaker posteriorly. The curvature of 
the ribs is unsymmetrical ; the anterior part curves raiiidly, the po.stero-dorsal 
part is only slightly curved. 

Ajfiidtiea. — A species from (lie .i-'enonian was figured and described by Goldfuss 



INOCERAMUS. 277 

as 7. fJrippxi, Mantel], and tliat idnitification lins l)oen accepted by many later 
writers. The type of I. Crippsi came from the Chalk Marl (zone of Schhimharhia 
varians). From a study of a cast of the type, Petrascheck and J. Bohm^ came 
to the conclusion that the Senonian species is quite distinct from /. Crippsi, and 
Bohm has named the former 7. halHcus. liohm also supports the view first 
suggested by Messrs. E. T. Newton and A. J. Jukes-Browne, and confirmed by 



\ 



\ 




Fig. 35. — Inoceranms Crippsi, Mantell. Upper Greensaml, Haldon. Right valve. British Museum (Xat. 

Hist.), No. L17201. Natural size. 

Petrascheck, that 7. Jatiis of Goldfuss and of d'Orbigny (but not of Mantel!) is 
identical with 7. Crippxi, IMantell. After a careful study of the type and other 
similar sj)ecimens of 7. Crippsi, and of si)eciiiiens of 7. latnx, I can fully support 
these conclusions. 

7. cinicifonnis, d'Orbigny,' is allictl to 7. Cvipp.^i, hui. is relatively higher. One 
specimen found in the Up})er Greensand of Warminster (Plate XLV II I, fig. ■^), 

1 ' Subhercyn. KreitKinul.lc ■ (1909), pj.. 41—4(3; PitiasiLeik, "luoceram. a. d. Gosau." • Jahib. 
(1. k. k. geol. Rcichsanst.,' vol. hi (1906), p. 155. 

- ' Pal. Franc. IVrr. Cii't.,' vol. iii (184C), p. 512, pi. cccevii. 

37 



278 CRETACEOUS LAMELLIBRANCHIA. 

sliows some reseinlilance to I. cHnciformis, but is probably only a rather liigli form 
of /. Crippi^i, with which species it is found associated. 

/. orhicnlarif, Goldfuss/ is regarded Ijy Bohm as a small form of /. Crippsi, 
Mantell. 

TiJ2)e. — In the British Museum (fig. So) from the Chalk Marl (zone of ScJilwu- 
hachia variant) of Off ham. 

DistrihiiJion. — Upper Greensand of Haldon. Upper Greensand (zone of Pecten 
aspcr) of "Warminster and Devizes. Chalk Marl (zone of SrJila'iihacltla rarian.i) of 
Ringmer, Hamsey, Oti'ham, Maiden Newton, Eggardon Hill, Tyrton, Chalton, 
Arlesey, Hunstanton, and Donnington (Lincolnshire). Cenomanian of Wilmington 
(Devon). Lower Chalk (zone of Hohtster suh(jlobosnii) of Totteruhoe, Burham, and 
Cherry llintun. 

Inoceramus CiMiM'si nir. iiKACiiENSis, Ethoridjc, 188L Plate XLVIII, figs. 4, b ; 

Plate XLIX, fig. 1. 

1881. Inoceramus IiKtus \\\r. rexchessis, B. Etheridje. In Peuuing and Jukes- 
Browne, Geol. Cam- 
bridge, p. 142, i>\. i, 
fig. 3. 

lie marks. — In this form, which is mainly characteristic of the zone of Ilolaxter 
anhijluhosus, the ribs are more sharply defined, their ventral curvature is greater, 
and their posterior part is less nearly straight than in I. CvippsL 

Tijpe. — From tlie Totternhoe Stone of Burwell, in the Sedgwick Museum, 
Caml)ridge. 

Didrlhnt'wn.— ChiAk Marl of Blue Bell Hill, Burham. Zone of Ualastrr snli- 
f/lohusiis of Merstham and Blue Bell Hill, Burham. Totternhoe Stone (zone of 
II. .snhijJdho.^iis) of Burwell. Recorded by Etheridge from the C-halk Marl of 
Reach. 

IiNouKKAMus Etiikimdcki, iiuiii. inic. Plate XLIX, figs. 2—4. 

1881. Inockramus convexus, ii. A'tlicrltlijc. In reniiing and Jukes-Browue, 

Gi'ol. Cambridge, [>. lio, pi. ii, 
fig. 6. 

— — — var. QUADRATUS, Etlieridije. Ibid., p. 1-13, pi. ii, 

fig. 7. 

— — STRiA'ivs wir. cunvEXVs, A. J. JiiJies-llroirne. Cret. Rocks of 

Briiaiu, vol. iii, p. 476. 

1 ' Polref. Gerin.,' vol. ii (1836), p. 117, pi. fxiii, fi^'. 2. Biihm, ' Subhercyu. Kreidemulde' (1900), 
p. Iti, pi. xi, fig. 1. 



INOCEKAMUS. 279 

Nou 18S5. Inoceramus convexur, J. JArZ/and F. /?. J/eei-. Foss. Cret. Nebraska (Mom. 

Amer. Acad. Arts and Sci , 
vol. v), p. 386, pi. ii, fig 2. 

Description. — Valves nearly oqiial, considerably iiierniilateral, tiimirl, compressed 
near the postero-dorsal mai'g'in ; lieit^lit greater than length. Antero-dorsal margin 
nearly straight; ventral margin usually very convex ; posterior margin slifhtlv 
or moderately convex, forming an ohtnse angle with the hinge-line. Anterior 
marginal parts more or less nearly perpendicular to tlie plane of the valves, some- 
times concave near the nmho. Uinbones terminal, curved inwards and forwards. 
Angle between the hinge-line and the anterior margin is about 115°. The hei'dit 
of the shell is nearly twice the length of the hinge. 

Ornamentation consists of faintly marked concentric undulations and numerous 
growth-lines. 

Affinities. — In this species the antero-dorsal margin is relatively longer and 
more nearly straight, and the postero-dorsal ])art of the shell less compressed thnn 
in J. tenim, Mantell. 

J. conve<i-nii var. fpuidratus, Etheridge, "was founded on a specime]i in which the 
antei'ior part of the shell is pressed in, giving rise to the appearance of a carina 
at the upper margin of the antero-dorsal slope. 

Types. — From the Totternhoe Stone of Burwell, in the Sedgwick Museum, 
Cambridge. 

Distnlivfion. — Upper Greensand (zone of I'erten a.^per) of "Warminster. 
Cenomanian of Wilmington, Devon. Chalk Marl of Branscond)e, Beer Head, 
Titherleigh (near Chan!) and Hunstanton. Totternhoe Stone (zone of Holastn- ' 
siihgluhosii.'i) of Burwell. 



Inockpamis I'lrrrs, Soverhij, ^ 829. Plate XLIX, figs. 5, 0. Text-fig. 30. 

1829. JyocERAiivs vic'ivs, J. de C. Soverly. Min. Conch., vol. vi, p. 215, pi. dciv, 

fig. 1. 
1854. — picTus, J. Morris. Cut. Brit. Foss., ed. 2, p. 170. 

1867. — ANGULATUS, E. Gvrraiiger. Album Pali'out. de la Sartbi', p. 

20, pi. XX V, fig. 7 (? I. ANQULATUS, 

trOiblyni,. 18-16). 
J904. — picTvs, E. T. Kill h, II \uu\ A.J. Ji(J.-iif-Bioiriie. In Jukfs-Browue, 

Cret. Kocks of Britaiu, vol. 
iii. p. 150. 

Jhscrij'tloii.—iihdl equivalve, very inequihiteial, slightly or moderately convex 
with flattened sides; the postero-dorsal part compressed. Antero-dorsal marginal 



280 



CRETACEOUS LAMELLIBRANCHIA. 



part flattened or concave, and more or less neai-lj perpendicular to the plane of 
the valves. Ventral margin very convex ; posterior margin moderately convex. 
Umbones terminal, incurved. Hinge-line nearly at right angles to the anterior 
margin. Ornamentation consists of nunierons strong, somewhat irregular concen- 
tric ribs, separated l)y concave interspaces. Tlie curvatui-e of the ril)s is 
unsyrametrical, and the ribs become less distinct on the antero-dorsal and postero- 
dorsal parts of the valves. 

Affinities. — This species shows some i-esemblance to I. amjlit-us, but possesses 
moi'e numerous ribs, and also differs in the anterior part of the shell being flat or 




Fio. 3(). — Inoreramus juXiis, Sow. Clialk Marl, (iuiklfoid. liritish Musmim No. 4'.i'21'2. Tlic Typo. 

Natural size. 



concave. The tyi)e and some other specimens (e. tj. No. 73339, British Museum) 
show traces of the original colouring of the shell. An example of this sjjecies 
was figured by Gueranger as /. ancjulatus, d'Orbigny,' but appears to be quite 
distinct fi'oin that form. 

Type. — From the Cluilk Marl of Guildford, in the British Museum (Natural 
History). 

Dixfrihiifion. — LoAver Clialk (zone of JTohtstor siibriJuhosHs) of Beachy Head, 
Burham, Kochester, and the Cog-ina-gogs, near Cambridge. Chalk Marl of 
Burham and Guildford. 

' ' Pal. Fiau^. Terr. Crct.,' vol. iii (1816), j). ill.S, \A. ccccviii, figs. 3, -i. lu the text the spelliug 
is ancjulosus. 



INOCERAMUS. 281 



Inocruamis i,\r;iATUs (l^chlnlheiiii), ISl:'.. Plato ],. Text-fio-. 37. 

1768. OsTRAClTES, J. K. I. Waleh. Dir Niiturgeseh. Vcrstciil z. Erlilul. d. 

Knorrischeu Saiiiiul. v. Mcrkwiinlij^'k. d. 

Natur., II, p. 8-t, pi. B 11/;*, fi^'. 2; 

p. 152, pi. dx, figs. 1, 2. 
1813. — LABiATus, E. F. V. Schlotheim. lu LeonliarJ's Taschcubuch 

fiir Mill., vol. vii, ]>. 93. 

PiNNITES DILUVIANUS, Sell hltliri III . IllilL, p. U'-j. 

1820. — — SchlotL'iiii. Potrefactenk., p. 303. 

1822. Mttiloides labiatus, A. Bi-ainjiiiitrt. Tu Cuvier, Ossomcus Fossil s, vol. ii, 

pt. 2, j.p. 320, .597, pi. iii, fig. 4. 

1822. Inoceramus mytilloides, (t. Manti-ll. Foss. S. Downs, p. 215, pi. xxvii, 

fit;. 3 ; pi. xxviii, fig. 2. 

1823. — MYTii.oiDEs, /. dc U. tiowerhij. Miu. Couch., vol. y, p. 62, 

pi. ccccxlii (not the two 
smaller figuies). 
1827. Catilltjm Schlotheimi, S. NiUson. Petrlf. Sueuaua, p. 19. 
1836. Inoceramus mytiloides, A. Gohl/uss. Petref. Germ., vol. ii, p. lis, pi. 

cxiii, fig. 4. 
? 1837. Catillus mytiloides, G. G. Pusch. Polens Paliiout., p. 45. 
1841. Inoceramus mytiloides, F. A. Rimer. Die Versteiu. il. uorJ-deutscli. 

Kreidegeb., p. 63. 
1846. — pkoblematicus, A. d'Orbiyny. Pal. Fraii^. Terr. Crct., vol. 

iii, jj. 510, pi, ccccvi, figs. 
1 — 7 {Non. I. jirohlemalicun, 
V. Schlotheim). 
— . — mytiloides, a. E. Reiiss. Die Verstein. der biihrn. Kreide- 

format , pt. 2, p. 26, pi. xxxvii, 
fig. 16. 

— — — H. B. Guinity.. Griuulr. d. Versteiu., p. 463. 
!'1847. — — A. d'Archiac. Mem. Soe. gi'ol. de France, ser. 2, 

vol. ii, p. 307. 
1850. — peoblematicus, A. d'Orbigny. Prodr. de Pal., vol. ii, p. 197. 

— — mytiloides, H. B. GeiiiUz. Das Quadersaiidst. oder Kreide- 

geb. in Deutschlaud, p. 176. 
'i 1852. — — F. BiJmer. Kreidebild. v. Texas, p. 60, jil. vii, 

fig. 5. 
1854. — — J. Mfirrin. Cat. Brit. Foss., ed. 2, p. 170 (jOTr/iwi). 

1863. — — A. v. Strombeck. Zeitschr. <1. deiitseh. geol. 

Gesellsch., vol. xv, p. 119. 

p 1870. latus, F. liiimci: Geo!, v. ()l>erschles., p. 316, pi. xxxiv, 

fig. 12. 
1871. _ LABiAius, F. ,Sf„llc:kii. Paluiout. ludiea, Cret. Fauna S. 

ludia, vol. iii. p. 40H. pi. xxix. 
Ck. 1. 



282 CRETACEOUS LAiyiELLIRRANCHIA. 

1872. iNOCEEAMrs LAiiiATUS, H. B. Geinitz. Das Ell)thalt|;fb. in Saelisen (Pal- 

oeontoijrapliica, vol. xx, pt. 2), 
p. 46, 1)1. xii, fi;,'8. 1 — 3. 

1873. — — Geinitz. Neiies Jalirb. fiir Mill , etc., p. 13. 
1877. — — C. SchllHer. Pala-outographica, vol. xxiv, p. 2(;2. 

— • — — A. Fritsch. Slucl. ini Grt-bieto der Ijiilmi. Krcide- 

forniat. ii, Weisspiibcr^'. \\. Malnitz. 
Sc'hicht., p. 130, fig. 112. 
^ 1888. — — -S'. Nilitiii. Les Vestiges Cn't. Euss. eentrale 

(Mum. Coniite gt'ol. Euss., vol. v, 
no. 2), p. 34, pi. 5, figs. 10, 11. 
1888. — —A. Peron. Hist. Terr, de Craie daus le S.E. du 

Bassiu Anglo-Parisien, p. 158. 
1893. — — F. Mirlinel. Zeitsclir. der deutsch. geol. Gesellsch., 

vol. xlv, p. 241. 

— — - T. W. Stn)iton. The Colorado Fonnatiou (Bull. 

U.S. Geol. Surv., No. 106), p. 
77, pi. X, fig. 4 ; pi. xiv, fig. 2. 
? 1897. — —It. Leonluinl. Kreideforiuat. iu Ober.schles. (Pal- 

fBoutograpbica, vol. xliv), p. 48. 
1903. — — TI^. Pftrasfhvcl: Jalirb. d. k. k. geol. Eeich.^au.st., 

vol. liii, p. 1,'J6. 

? Nou 18C8. - MYTihoiDES, E. Ficliwuld. Letlia?a Eossiea. vol ii, p. 492, pi. 

xxi, fig. 6. 
-— 1881. — (Mttilites) rROBLEMATicus, R. Etheridije. In Penning and 

Jukes-Browne, Geol. Cambridge, 
p. 143, pi. iii, figs. 9— 11. 

De.'tcripfinn. — Shell inytiliform, nearly cquivalve, extremely inequilateral, 
oblique, much elongated between the umbo and the postero-ventral extremity, 
convex, with a small posterior ear ; aiitero-dorsal part sloping steeply and some- 
times concave. Angle formed by the hinge with the antero-dorsal margin about 
90°. Umbones terminal, with a slight antei'ior curvature. Anterior margin gently 
curved; postero-ventral extremity very convex; posterior margin nearly straight. 

Ornamentation consists of small, fairly regular concentric undulations, which 
have an unsymmetrical curvature in the young, but become more nearly symmetrical 
in older specimens. On the old i)arts of the shell the undulations become less 
distinct. 

AflinificK. — It seems probable that this species is related to /. Crijijisi var. 
rcachensis (p. 278), but the height of the shell is relatively greater, the length of 
the hinge-line is less, and the direction of growth is oblique to the hinge-line. 

/. pwpiiupius, Goldfuss,' from the Quader-sandstone of Schandau, Avns regai'ded 
by Geinitz as a sj'nonym of I. lahidiii.'i. 

1 ' Petref. Germ.,' vol. ii (1836) p. 112, jil. cix, fig. H. 



mOCERAMUS. 



283 



D'Orbigny identified this species with /. prohlematicits, von Schlotheini, which 
comes from the Senoniai:, and has been shown by Bolim to be distinct from the 
Tiu'onian form.^ 

lieniarks. — This species is mainly characteristic of the zone of lih[/nch<jiicUa 
Cavieri. In the zone of Terehratuliua lata it is not common, and the shell is 
nsually relatively longer than in typical forms of the species. 

TijiK-s. — The type came from the Turonian of I'irna. The sjiecimens figured by 
Man tell from the zone of Blujuclionella Cavieri of Pliimpton are in the British 
]\fnseum. The large specimen figm-od by Sowerl)y fi'om AVarminster cannot 1k> 
found. 

Diiitribiitlon. — Zone of Bh//urJtoncll(t Cavieri of the Devon and Dorset coasts, the 
Isle of Wight, AVinchester, Eastbourne, Lewes, Plumpton, Dover, Blue Bell Hill 
(Burham), Betchworth, Watlington (Berkshire), Hitchin, Cherrj' llinton. South 
Thoresl)y, South Ferriby (Lincolnshire), antl the Yorkshire coast. Zone of 
Tcrehratnlhiii lain of the Devon and Dorset coasts, Winchester, Eastl)ourne, and 
Dover. 

Recorded by Jukes-Browne from the zone of Holaster sub(jlohosas of Cambridge- 

FiG. 37. 




Fio. 38. 



•i^-. 




:^ 



Via. til.—Inoceramus laiialus (Schloth). Tlio typo of Inoceramus mylilnides, MautfU, ' Foas. S. Downs,' 
p. 215, pi. xxviii, fig. 2. Zone of K/nyiic/ioiicHu t'lii-icrt. Plumpton. Ui-itish Miisfum. Nntunil size. 



ipton 
Fio. 38. — Inoceramus labia/us vjir. hihis, Sow. Zoiio of lli>hisf,i- iilnnns, ruik-y Junctioa Station. 

Musuuni, No. L211'J1. Natiu-.il sizf. 

1 J. Bolini, ' Moiiatsber. d. d.;utsch. gwl. Gesellsch.' (ll}Oi>), p. 117. 



British 



I 

I 



284 



CRETACEOUS LAMELLIBRANCHIA. 



sliire and West Norfolk ; ami 1)y Rowe from the zone of Holaster j;/«j(»s of Dover 
and tlic Sussex coast, and from the zone of Mirraslev cor-tc.stndinnrium of Dover. 



Fiu. 39. 



Fk!. 40. 






Fig. 3"J. — hioceramus labiatus var latus, Sow. Zone of Hohister p/miiis, Swafl'ham, Norfolk. Nonvich 

Museum, No. 329(5. Eight valve and anterior view. Natural size. 

Fig. 40. — Inoceramvs labiatus var. Intvs. Sow. One of tlie types of Iiwceramvs latus, Sowerljy, 'Min. Conch.,' 

vol. vi, \i. I"i9, pi. ill.\.xxii, fig. 1 (lower figure). Swaffliam. British Museum, No. 43266. Natural size. 



Inoc'ER.uiiis i,.\ hiatus var. i,atus, SuirerJi;/, 1828. Text-figs. 38 — 40. 

1828. Inoceramus latus, /. du C. Soirerhij. Miu. Couch., vol. vi, p. 15ft, [,]. 

dlxxxii, fig. 1. (Noil /. hili/s, 
Mantell). 

1854. — —J. Morris. Cat. Brit. Foss., ed. 2, p. 170 itnuilni)- 



TiriiKirls. — Tliis variety differs from /. luhinhi^ in the much greater length of 
the hinge-line in proportion to the height of the shell, in the greater convexity of 
the anterior margin, the smaller convexity of the ventral margin, and the less 
oblique form of the shell. On account of the greater length of the hinge-line the 
curvature of the ribs and growth-lines is broader than in /. luhidtns. 

This vai'iety appears to be confined to the zone of Ilolastev plaitit.'t, and is 
common in the neighbourliood of Swaffham, Norfolk. The larger specimens which 
I have seen are not sufficiently jierfect for figuring, but a characteristic exam^jle 
is figured by Sowerliy. 

Types. — From the zone of IJoIa.^fer planus of Swaffliam. The smaller specimen 
figured by Sowerl)y is in the British IMuseum (Fig. 40), but the larger specimen 
cannot be found. 

Distrilmfion. — Zone of Ilolaster iilaniis of Purley Junction Station, Surrey, and 
SwalTham, Norfolk. 



Ipalaeontoovapbical Society, \o\\ 



A MONOGRAPH 



CRETACEOUS LAMELLIBRANCHIA 



OP 



ENGLAND. 



BY 



HENRY WOODS, M.A. 

UNIVERSITY LECTURER IN PAL^OZOOLOOT, CAMBRIDOE. 



VOL. II. PART VIII. 
INOCERAMUS {continued). 
Pages 285— S-iO; Plates LI— LIV. 



LONDON: 
PRINTED FOR THE PAL^ONTOGRAPHIC AL SOCIETY. 

1912. 



PRINTED BY ABLARD AND SON, LONDON AND DORKING. 



INOCERAMUS. 285 






Fio. 41. — Inoceramus lahialus viii\ latiis. Sow. Zone of Holaster 2>l''>i>is, Coombe Bissett. Dr. Blackniore's 

Collection. Right valve. Natural size. 

Inoceramus inconst.vn.s, sp. nov. Plate LI, figs. 1 — 4. Text-figs. 39, 42 — 49. 

1822. Inoceramus Brongniarti, var., G. ManteU. Foss. S. Dowus, p. 215, pi. 

xxviii, fig. 3. 
— — SP. Maniell. Ibid., p. 217, pi. \xvii, fig. 9. 

1850. — Lamarckii, J. de C. Sowerlij in F. Dixon. Geol. Sussex, p. 

355 (p. 385, ed. 2), 
pi. xxviii, fig. 29. 
1904. — Brongniartii, C. Airajhi. Boll. Soc. geol. Italiana, vol. xxiii, 

p. 192, pi. iv, figs. 3—5. 

Description. — Shell extremely inequilateral, moderately or slightly inequivalve; 
the early part of the shell slightly convex or nearl\' flat, the later part much more' 
convex and sometimes growing nearly perpendicularly to or forming a large angle 
with the early part, so that in old individuals the shell liecomes more inflated ; in 
other cases the convexity increases more gradually from tlie earlier to the later 
stages of growth and a nearly glolxise shell results. Height of the shell often 
rather greater than the length. Hinge-line long, forming rather more than a 
right angle with the anterior margin, which is usually more or less nearly straight. 
Ventral and posterior margins rounded. Umbones terminal, small, jjointed, only 
slightly curved. Anterior marginal part of the valve usually flattened, but not 
definitely limited from the sides of the shell. Posterior ear developed but not 
distinctly limited. 

Concentric folds are usually well developed, l)ut ])cc()me indistinct on the 
anterior flattened area, on the posterior ear, and on the later part of the valve 
of old individuals. The concentric folds have a very unsymmetrical curvature. 

Remm-hs. — The forms iuehuled in this species vary consideral)ly, owing mainly 
to the length of duration of the flattened stage, which in some individuals forms a 

38 



286 



CRETACEOUS LAMELTJURAXCII lA. 



small part (Figs. 4:5, 48, 4'.») l)ut in others a large part (Plate LI, fig. 2, Text-figs. 
45, 4(5) of the eiitii'(> shell.' Also the passage IVom one stage to tlie other is 
sometimes gradual, so that the section ol" the shell t\)i'nis a fairly miiform eui-ve 
(Fig. 48), but generally tlie change is abrupt, so that the later part of the valve is 





Fifi. 42. — Inocei-amus imuustans, sp. iiov. The orisjinal of I iioceramus sp.. Manti-ll, ' Foss. S. Downs,' p. 217, 
pi. xxvii, h'r. y. Ujjpor Chalk, Lowes. Britisli Musoum, No. -ilO-'). Left valve and posterior view. 
Natural size. 




>_>*'' 





Fia. 43. — Inoceramus incoHslttns, sp. nov. Zone of Holaster planus, Swall'hain, Norfolk. Norwirli Museum. 
Left valve, and posterior and dorsal views of the same. Natural size. 

bent at an angle with the earlier part (Figs, l-^, I-!). The length of the hinge-line 
in proportion to the height ot" the shell shows some variation and conse(piently the 

' Tlio larger spcciiucu of I. hifii:i, Sowcfliy (' Mill. Coueli.,' vul. vi, pi. dlxxxii. ujjper figure), 
■which eanuot uuw be foiuid, is ja-oliulilv an example of this. 



Fi<;. I.-. 



Fig. 44. 






Fio. 4ri.—Inoce)-amus inconshins, sp. nov. The oiiifinal of /. llmitjuiarli, var., MaiitcII, ' Foss. S. D.iwns," 
p. 215, pi. x.xviii, fijj. 3. Upper Clialk (prol)al)Iy zone of Mirraster cur-aifiiiinum), Soutlieraui. British 
Musevim, No. 5878. Right valve. Natural size. 

FiQ. 4r,.—Inoceramus mconsfaiis, sp. nov. Upper Chalk, Sil-sslx. liritish Jliiseum, No. 5861). Left valve 

and anterior view. Natural size. 




Fio. -Mi. — />i Off rum lis I'neonii'nii.'i, sp. nov. Zone of Hiihtnler j'/niiii.i, SnafTliani, Norfolk. Norwioh Miitioum. 

Right valve. Natural size. 



288 



CRETACEOUS LAMELLIBRANCHIA. 



curvature of tlio I'ibs varies. In some specimens (often of large size) the shell 
is thinner tlian usual and has sharp and ridge-like folds similar to those of 
7. Lamarcld var. Wi-bsteri, Mant. (p. 818). Further work may show that it is 
desirable to eive names to some of the varieties of I. inconstans. 

Affinities. — This species is closely allied to /. hihiatns var. lafus, Sowerby;' 
but the hinge is relatively longer and the height of the shell less, the anterior 
flattened area is larger, the later part of the shell is more convex, the umbones 
ai'e less jirominent and the posterior ear more distinct. 



.#■.-.-• \Vi9'.^3r ■ mr-.—Ja 






Fig. -t". — Inocevamus iticnnstans, sp. nov. Upper Chalk (zone of Actinocamax quadratiis), liii|^')iton. 
Brighton Museum, No. 336. Right valve and anterior view. Natural size. 

7. incon,<itan>i is distinguished from 1 .Lamarclci, Parkinson (p. 807), by the 
relatively longer hinge-line, the more unsymmetrical curvature of the folds, the 
flattened form of the early part of the shell, the less prominent umbones, and 
tlie smaller difference in the size of the valves. 1. Guvien of Andert" appears to 
l)e a flat form of /. inconstans. Another specimen figured by Andert'' is allied to 
7. ineonstivutt, but its a.xis of growth is more ol)lique and its hinge longer than usual. 

1 Erratum ou p. ^84 (fig. 39) : for Tvoceramvn Jahiatus var. latug. Sow., read Inoceramns incon- 
stayis, sp. uov. A specimen figured by Audert (' Inocerameu d. Kreiltitz-Zitfavier Sandsteingeb.,' 1911, 
]). 45, pi. i, fig. 5) as I. Cuvieri var. planus appears to be iuterinediate between I. lahuitita aud/. labiatus 
var. latus. 

~ Loc. cit., pi. ii, fig. 2. 

' Loc. cit., pi. i, fig. 2, pi. vii, fig. 8 (/. Cuvieri var. ^'/("(".s). 



INOCERAMUS. 



289 





"^^S^i^^ 




Fiu. -IS. — Inoceram'is iHcoiisdiHS, sp. iiov. Upper Chalk. Ijowility unknown, lliitisli MiisiMiiii, No. 3<WS2. 

lA'ft valve and dorsal view, x \. 



2; 10 



CRKTACEOUS LAM i:i.I>IHRANCHIA. 



J 






Fig 49— Inoccra»ms iHf..«s/..ii.s-. sp. nov. Zone of Adinocomax qnml mtus. East HiirnlKim, Salisbury. Hr. 
Blackmoro's CollLc4ion. Left valve and dorsal view. Natural size. 



IXOCERAMUS. 291 

T///ics.~ 'V\\o specinieii Hgured by Aiaulull as /. JlniiKjuiarfi x-.w.. IVoin tlu' Upper 
Clmlk (pnil)alily zone of Micrastrr cor-aiKjtiimim) of Soutliei'am (l^cwes), and tlie 
one Hiiurcd as Liof'ninin^i sp. l)y tlu' same antlioi' from Lewes, and /. Lt iu(trrl-'i, 
S()\vt>i-l)y (in Dixon), fVoni tlie Chalk, Snssex (prolmbly zone of Trirhrnlnliud. 
lif'i of ]\[allino-"), ai'e in tlic British ]\fus(Mim. Xos. -5878, I7l>'>, li'Jolt-V) I'csncct ivclv. 




Fig. oO — /«o<cioi)i»s iiicoMs/oiis, sp, nov. var. Sriioiiian. Haldon. Uritish Museum, Xo. LlTySO. Left valve. 
A large flat form resembliug /. cijdoides, Wegner. Compare with Fig. 4(i. x J. 

Distribution. — Zone of Ifiiln-sfc)- iihiiias of Twyford, Swaffliam (Xorfolk), anil 
Strood. Zone (if Mirvustur cor-ti'ntiiiHintriinii. of C'lintliam, Guilford Colliery 
(Coldivd near Dover), and AVlianam (^'orkshire). Zone of Micraster cor-an<jniiiiuii 
of Soutlieram (Fiewes). Zone of Acfiiioc((m((,i: rjuadratits of East Harnliaiu 
(Salisbury) and lirighton. Zone of Bcleinuitdla vincronata of Siiiile (Isle of 
\Vight). Probaljly also in the zone of Terebnitalina lata. 



292 CRETACEOUS LAMELLIBRANCHIA. 



Inoceeamus inconstans frtr. stkiatis, Mmtti'Il, 1822. Plate LI, fig. o ; Plate Lll, 

1822. Inoceeamus strixtvs, G. Mantell. Foss. S. Downs, p. 217, pi. xxvii, fig. 5. 
1828. — — J. de C. Sotverby. Min. Condi., vol. vi, p. 160, pi. 

dlxxxii, fig. 2. 
1854. — — J. Morrii<. Cat. Brit. Foss., ed. 2, p. 170 (jwW/m)- 



Nou 1836. — — A. GoZ(//'».s8. Petref. Grerm , vol. ii. p. ll-l. pi. c.\ii. 

tig. 2. 

— 1841. — — F. A. Itiimer. Die Verstein. cl. uord-dentsdi. 

Kreidegeb , p. 62 

— 184C. — — A. E. Reasg. Die Versteiu. der boluu. Kreidi'lor- 

mat., pt. 2, p. 25. 

— 1846. — — A. (rOMijnij. Pal. Frauc. Terr. Cret., vd. iii, p. 

508, pi. ccfcv. 

— 1850. — — d'Orbigiiy. Prodr. de Pal , vol. ii, p. 168. 

— 1852. — — F. Romer. Kreidebild. v. Texas, p. 60. 

— 1868. — — A. V. Strombecl-. Zeitsdir. d. deutscb. geol. Gesell- 

seli., vol XV, p. 108. 

— 1863. — —A. Kunth. Iliid., vol. xv, p. 727. 

— 1870. — — F. R'iiner. Geol. v. Oberschlesieu, p. 340, pi. xxix, 

fig. 6. 

— 1872-73. — — H. B. Getnitz. Das Elbtbalgeb. iu Sadiseu (Pal- 

aeontographica, vol. xx, pt. 1), 
p. 210, pi. xlvi, figs. 11—13; (ibid., 
pt. 2), p. 41, pi. xiii, figs. 1, 2, 
It, 10. 

— 1873. — — Geinitz. Neues Jalirl). f iir Min., etc., p. 7. 

— 1877. — — A. Fritsch. Stud, ini Gebiete der bijhm. Kreide- 

forinat. ii, Weissenberg. u. Maluitz. 
Sdiidit., p. 120. 

— 1881. — — J. Kiesow. Sclirift. nat. Gesellseh. Dautzig, vol. v, 

p. 413. 

— 1885. — — F. NiitUiifj. Die Fauna d. baltisch. Cenoman. (Pal- 

aeont. Abhandl., vol. ii), p. 23, pi. iii, 
figs. 11, 12. 

— 1893. — — R. Michatl. Zeitschr. d. deutsch. geol. Gesellscb., 

vol. xlv, p. 233. 

— 1895. — — E. Tiessen. Ibid., vol. xlvii, p. 480. 

— 1897. — — H.Woods. Quart. Journ. Geol. Soc, vol. liii, p. 381, 

pi. xxvii, fig. 13. 

— 1911. — — A. Fi-itsch. Stud, iin Gebiete biihrn. Kreideformat. 

(Ergiinzuug zu Bd. I, Korycaner 
Schidit.), p. 42, fig. 190. 



INOCERAMUS. 293 

Uoimii-s. — This variety, wliicli is uncommon and of small size, is distinguished 
by the strongly inflated valves, tlie large angle between the hinge-line and the 
anterior border, tlie absence of folds, and the absence or indistinct character of 
the anterior flattened area and of tlie posterior ear. 

Tijpes. — The type, from the zone of Mlcnisfer cor-inKjniitinn of Soutlierani, 
Lewes, is in the British Museum, No. 47G8 (Plate LI, fig. 5). Tiie specimen 
figured by Sowerby from the Upper Chalk (probably zone of Uolasfer planus) of 
Heytesbury is also in the British Museum, No. 4o267. 

Distribution. — Zone of Holaster 2)la)ius of Stonelmll siding near Dover, and 
Swaffham, Norfolk. Zone of Micraster cor-angninum of Southeram. Upper 
Chalk (probably zone of Holaster idanus), Heytesliury. 



Jnoceijamls ixcoxsTANs (;((/'. sAiJLMKXsis, cur. nor. Plate LIL tio-s. 2, o. 

A variety found in tlie zone of Actinorama.r (juiolratus of East llarnham 
(Salisbury), Mottisfont, and "West Meon (Hampshire), is distinguished bv tlie 
uml)ones being more prominent and not terminal, by tlie regular convexity and 
equal size of the valves, the absence of tlie anterior flattened area, and the absence 
or indistinct character of the concentric folds. This variety is connected with 
typical forms of the species by some examples (Fig. 49) in which the earh' part of 
the shell is less convex and possesses di-stinct folds, but the nmbones are not quite 
terminal and tlie anterior flattened area is not present. J. inconstans var. 
narumensls appears to resendile T. Brancoi, "Wegner," of which good figures have 
not yet been luiblished. 



Lnoceramds liAi/ricus, lidhm, 1907. Text-figs. -jI — ')■}. 

183(5. Inoceramus Cripsii, A. C^''</<(/'«^•(?. Petref. Gt-rm., vol. ii, \i. 116, pi. cxii, 

fig. 46. (Nou I. Crippsi, Mantell, 1822). 

1870. — — var. SULCATA, i''. i?.i;»f)-. Geol. v. Oberschles., p. 35<). 

p!. .\xxi.\, fig. 9. 

1907. — BALTicus, /. Bi'ihm. Zfitsclir. il. deutscli. geol. Gesellscli., 

vol. lix, Mouatsber., p. 113. 

1909. — — /?.;/(<*(. Sublu'ivvn. Kroidfiiiul.le (Alihan.ll. .1. k. 

]ir«.'Uss. geol. Laiulesaust ; n.f. 5G), p. 47, 
pi. xi, fig. 2a, pi. xii, fig. 1<(. 

1910. — - .1. Noii-iih. J{iill. Intemat. Acad. Soi. Cracovie 

(1909), p. 875. 



' ' Zt'itsclir. d. deutsch. geol. Gesellsch.,' vol. Ivii (1905), p. 159, fig. 4. 

39 



294 



CRETACEOUS LAMELLIBRANCHIA. 



Description. — Shell equivalve, ver}' inequilateral, slightly or moderately convex, 
becoming ver\- convex in old specimens, in which the later part of the shell grows 
either perpendicularly to or at an obtuse angle Avith the earlier part ; posterior 




'^^-^. 




Fio. 51. — Inoceramus haltints, Biiliiii St'iioiiian, Worbarrow Bay, Dorset. British Museum, Nu. L:;2177. 
J'lint cast. Ri"-lit valve ami anterior view. Natural size. 




Fia. 52. — Inoceramus lalticus, Bulim. Anterior view of specimen shown in Fi<^. 53. x J. 

and postero-dorsiil pai'ts compressed; length greater than height, the difference 
increasing with age. Anterior and ventral margins rounded ; posterior margin 
forming an obtiise angle wath the hinge. Hinge-line long. Umbones rather 
small, nearly terminal. 



INOCERAMUS. 



295 



Concentric ribs strong, sliarp, narrow, witli a very unsymmetrical curvature ; 
a few ribs may come off from the sides of otlier riljs; between tlio ribs are broad 
concave interspaces. On the marginal ])arts of okl specimens ribs are absent. 

Affinities. — /. hiillirns is closely allied to f. inronsfuns, IVom whic-li it lias 



' ) 



X 



\ 






\ 





Via. 53.— /iiofei-aniiis hiilticus, Buhiii. Upjx^r Cliiilk (proliiiWy zone of Mannpiles testudinarius), Brighton. 
Mtisoiiiii of I'nioticiil Oeology, No. 2.).jO!». I,i>ft valve .iiul dorsjil view, x }. 

probably been derived; it differs from that species by its longer hinge and the 
longer shell, with the umbones not quite termin;il. The length of duration of the 
slightly convex stage varies in the same way as in /. incini.'itdii.t. The specimen of 
/. iiu-oiisftin.'i .shown in Fig. 40 makes, on account of its longer hinge, some 
approach to /. balticus.^ 

' See also Bubiii, loo. cit., pi. xii, fig. Id. 



20(5 CRETACEOUS LAMELLIBRANCHIA. 

J. reijuhirix, irUrljignj',' differs from J. hdlticns in the outline of the t^liell, in its 
uniform convexity, and in tlie broader and less sliarp ribs. 

Some of the foi'nis fi'oni (i(i.-<au refen-ed l)v Zittel to /. Grifpsi resemble closely 
I. halti'cns." 

Tjipc. — From the Lower Quadrafn^! beds of Diilnien, in the Paheontologicid 
Institute of the University of Bonn. 

DutribiilvDi. — Senonian of Haldon, and \Vorl)arro\v Bay (Dorset), and Brighton 
(probably zone of Mnrsupitcn fcHfiKTuiarius). Zone of Arthiocnmax qiimhrifHs of 
Mottisfont, Ropley (Hants), East Harnhani (Salisbury), Mount Pleasant near 
Andover, Driffield, and Se\verl)v (Vurkshirej. Zone of iirli'muiti'lJii nnh'tuii/iitu nf 
Clareiulon and Farehani (Hants), Alum Bay and SJiide (Isle of Wight), and Xorwieli. 

Inocehamus LOHATrs, <li,](lfiif<^, IS:')*;. Text-figs. 5J-, 55. 

1836. Inockramus lobatus, A. Gohlfiiss. Petref. Grenii., vol. ii, \>. 118, jil. ex, 

fig. :J. 
1877. — — C. Schliifer. Palajoutograpliica, vol. xxiv, p. "27.5, 

pi. xxxix, figs. 1, 2. 
1882. — ~ H. Schnuler. Zeitsuhr. d. deutseb. geol. Gesellsclj., 

vol. xxxiv, p. 272. 
? 1888. — !.ff. LOBATL's, S. NiA-itiii. Los Vostiges Crc't. iliuis la Kussie 

Centrale (Mem. Coniite Gi'ol., 

vol. V. no. 2), p. 'SI, pi. V, fig. 12. 

— — LOBATUS, G. Mailer. Jabrli. d. k. preuss. gcol. Laudesaust. 

fur. 1887, p. 415. 
1889. — — E. Hohap/rl. Die Mollusk. Aachen. Kreide (Palse- 

outographiea, vol, xxxv), p. 228. 
? 1894. — all. LOBATUS, K. Jimho. Kreideforuiat. v. Hokkaido (Pal- 

seout. Abliaudl., vol. vi), p. 44, 
pi. viii, fig. 11. 
1898. — LOBATUS, (/. Mullet-. Mollusk. Uiiterseu. v. Braunschweig, n. 

Ilsede (Abhandl. d. k. preuss. geol. 
Laudesaust., n.f., 2.5), p. 43, fig. 10. 
■rl9Ul. — cf. LOBATUS, i'\ iS7«(///. Jabrb. d. k. preuss. geol. Laudesaust. 

fur 1900, vol. xxi, p'. 93, pi. x, fig. 3. 
1902. — LOBATUS, A. Wolli'iiuiiiii, Liiueburg. Kreide (Abhaudl. d. k. 

preuss. geol. Laudesaust., n.f.. 37), 
p. 71. 

1 ' Pal. Frau?. Teir. Cret.,' vol. iii (1846), p. 516, pi. ccccx. 

- Compare also /. Crij)gi var. sulcata, Eomer, 'Kreidebild. v. Texas' (ls52), p. 56, pi. vii, fig. 2, 
aud I. Crijisianug, Stoliczka, 'Pala?out. Indica, Cret. Fauna S. ludi.i,' vol. iii (1871). p. 405, 
pi. xxvii, figs. 1 — 3 ; pi. xxviii, fig. 2, aud T. crassiis, Petraseheck, ' Jahrb. d. k. k. geol. Eeicbsaust.,' vol. 
liii (1903), p. 164, pi. viii, fig. 4, aud Andert, ' Inocerameu d. Kreibitz-Zittauer Sandsteingeb.' (It'll), 
p. 46, pi. iii, fig. 4, pi. vi, figs. 1, 2. 



IXOCERAMUS. 



2!>7 



1902. IsoeKRXMUs LoiiXTVi J. P. J. Utni. M.>llu>k. i Diuiiiiuilcs Kridtafl. I. 

L;iiiirllil>r., p. lOo. 
1C)0.5 — — T. Wefjiier. Zeitschr. <1. dcutsch. f,'eol. Gesellsch., 

vol. Ivii, p. Itit, fit,'. 7, pi. X, figs. 1, i, 
and text- fig. 7. 
ic»0(!. — — G. Siiiol,!id-l. Bull. luteriiat. Acad. Sci. Cracovi'-, 

p. 722, pi. xxvii, figs. 16-18. 
l;i(»'.i. — -- J. Kuind: Ihi.l (19Ui<). p. 875. 




Fio. 54. — /noreraiiiiis lobalui, GoUlf. Zime of Artinoeamaz quadratut. East Leys, Yorkshire. BritUli Miisvuni, 
No. L23itHl. Iiitfiiiiil cnst of rijjlit viilve; p isterior wing missin);. x J. 



Ih-srrijilinii. — Shell very im'i|iiilatcr;il, (^^{(iiic, compressed, sliuflitly eoiive.x — 
till' anterior juirt iiinrc coiive.K tiniii llic posterior part; nuicli Iiij,^]ier tliaii Ioiil,'. 
Aiitero-dorsal marginal pait .sloping steeply. \'entral margin eonve.x, with a 



298 



CRETACEOUS LAMELLTBRANCHIA. 



shallow .sinus near the postero-ventral angle. Posterior margin nearly straight, 
somewhat oblique, forming an angle with the ventral margin. A broad shallow 
depression extends from behind the umbo to the postero-ventral sinuosity ; 
posteriorly this depression is limited by an angular ridge. Behind the ridge is a 




Fig. 



-Jnocerainus lobaius, Orolilf. Zone of Actiiiocumax qiKulraliis, Yorkshire. York Museum. Part of 

left valve. x |. 



flattened or slightly concave wing-like part which, owing to the thinness of the 
shell, is often not preserved. Umbones acute, near the anterior end. 

Ornamentation consists of concentric ril)S with an unsymmetrical curvature ; in 
the posterior depression the ribs bend upwards, forming a sinuosity, and on the 
wing the ribs bend upwards and are less distinct than elsewhere. The concentric 
ril)s are of two sizes ; large ribs occur at intervals and between these are several 
sinallcr ril)s. 



INOCERAMUS. 209 

Affinities. — Lioceramtis nasiitti.'^, Wegner,' from the iSeiionian of Bosseiulorf and 
Di'ilmeii, is allied to /. hihafus. See also /. li)itpia, T. cardigsoiJesynwd 1. inJn^rculntus 
(below). 

RemorJrs. — Only iiii[iei I'ect casts of tins species have been seen, but it is 
almndant in Yorkshire. In North Germany this species occurs also in the zone of 
Marsupites testudinanns. 

Type. — From the Lower Senonian of Quedlinburg. 

Distribution. — Zone of Artiiinrmini.f qmidrattoi of Sewerln', Bessingby and 
other localities in Yorkshire. 



InOCEEAMUS LINGVA, GoJdfmii, \^'M\. Text- fig. 56. 

183(j. Inoceramus mngia. A. Guhlfiiff. Pttref. Germ., vul. ii, \<. 113. j.l. c-x, 

Hg. 5. 
1877. — — C. Schhiter. Palseontograpliicu, vul. x.\iv, p. 270, 

])I. xxxix, tigs. 3, 4. 

1898. — — G. Mailer. Mollusk. Uuterseii. v. Brauu.sehweig. u. 

Ilsede (Alihandl. d. k. preiiss. geol. 
Laudesanst., n.f., 23), p. 4-5, pi. v, 
fig. 8. 

1899. — — V.Popovicl-Hatzeij. Mi'in. Soe. gt'ol de France, Pali'ont., 

vol. viii, pt. 3, p 7. 
1902. — — J. P. J. Rant. Mollusk. Daumarks Kridtafl., I. 

Laiuellibr., p. 102. 
19u5. — — T. Wegner. Zeitschr. d. deutsch. geol. Gesellsdi., 

vol. Ivii, J). 168. 
19u9. — — /. Noicak. Bull. Iiiteruat. Acad. Sci. Cracovie, p. 875. 

Remnrks. — Thi.s species is clu.sely allied to /. loliatns, Goldfuss, but the speci- 
mens at present available are not sufficiently perfect to enable me to make a close 
comparison. /. liiiffiia appears to differ from /. lobatu.^ in the absence of the ridge 
between the umbo and tlie postero-ventral angle, in the absence or indistinct 
character of the radial depression in front of the ridge, in the greater relative 
length of the shell, and in the ribs being either of uniform size or of two sizes less 
distinctly niiirked than in 1. lubninsi. 

Type. — From the Senonian of Diilmen. 

Distribution. — Upper Clialk of Birdsall, Yorkshire. Zone of Bclemititelln 



> 'Zeitschr. d. deuUch. geol. Gesellscli..' vol. Ivii (1905), p. lt>7. pi. x, fig. 3, text-fig. 8. 



:5O0 



CRETACEOUS la:\ielijbranchia. 



tiicroiuda uF Xorwich. llccoidcd l)j Barrois from tlie zone of Mar.-nipites 



te.'itiuUnarin.'< of Rottingdean. 




Fio. 50. — Inoceramus Ihiyiia, <!oI(lf. Zone of Belemnilella mucronata, Norwich. British Miisouiii, No. 

L2oy56. Part of riufht valve. Natural size. 



Ino('i;i!.\mi!s cMiPissoiiiKs, (lohlfitsfi, 183G. Text-fig-s. 57, 58. 



1836. Inoceramus cardissoides, ^. Go/f(/'«.sjj. Petref. Gt'iiii., vol. ii. j). 11"2, 

pi. ex, fig. 2. 
18-41. — LOBATUS var. /i. CABDissoiDES, J". .(4. i?n»ier. Die Verstein. 

d. nord-deutscli. Kreidegeb., |'. ti'S. 
187(i. — cxnvisnoxnES, I). Bnuina. Zeitsehr. f. d. gesainiiit. Natur- 

wiss., vol. xlvi, [I. 377. 
1877. — — G. Schiater. Palaeoutographica, vol. xxiv, p. 274. 

1888. — — G. Mailer. Jahrb. d. k. prouss. geol. Lau- 

d.'saust. fiif 1887, p. 415. 
1898. — — G. Miillev. Mollusk. Unterseu. v. Biaun- 

schweig u. Ilsede(Abliaudl. d. k. 
prt'uss. geol. Laudesaiist., n.f., 
25), i>. 44, fig. 11. 
19o2. — — A. WoUemaun. Liiueburg. Kreide (lb d., 37), 

p. 71. 
1905. — — T. U'eyncr. Zeitsehr. d. deutsch. geol. 

Gesellscli., vol. Ivii, p. 109. 



IXOCERAMUS. 



301 



Nou 1882. Inockkamus cardissoides, H. Schroder. Zeitscbr. d. deutscli. geol. 

Gesellscb., vol.xxxiv, p. 271, 
j>l. xvi, fig. 1. 

Dei^criplion. — Sliell very inefniilatcral, oblique, moderately convex, -with the 
anterior marginal part sloping rapidly. Height considerably greater than length. 



Fta. 



Fio. .-)S. 



\ 



^r 



.y 



UC^^•'■■'- 



p5^''^. . > 








f f, 





Fia 57 -7»ocei-amus cardissoides. Goldf. Upper Chalk (proKably zone oi ActinocauKix quadratus). near 

Speeton. Sedgwick Museum. Left valve. Posterior wing missing. Isatiual size. 
Fio 58 -/no«.-a.»iis cardissoides. Uoldf. Upper Chalk, probably Kent. British Museum. No. 98209. 

Part of left valve. Natural size. 

Ventral margin convex; anterior margin slightly curved. A broad concave 
depression extends from behind the umbo to the postero-ventral extremity, and is 
limited posteriorly by a straight, sharp ridge, behind Avhich is a wing-like part of 
the shell. 

Ornamentation consists of strong, widely separated concentric ribs, with a steep 
ventral slope and a more gentle dorsal slope; in the interspaces are small con- 
centric ribs, which arc crossed by small radial ribs giving a more or less distinctly 

40 



802 CRETACEOUS LAMELLIBRANCHIA. 

tuberculatc cliaracter to the larger concentric ril)?. On the posterior part of the 
shell the concentric ribs bend sharply npwards. 

Bcmarls. — Only two imperfect specimens of this species have been seen ; it is 
closely allied to I. Inhalnx (p. 29G), but differs in the presence of radial ribs, the 
greater development of the larger concentric ril)s, and in the greater convexity of 
the valves. 

Tiiiv'. — From the Senonian of Quedlinlnirg. 

Distribution. — Upper Chalk ([)robably zone of ^Irtinoi-intia.v ijinatrafus) near 
Speeton, and the sonth of England (probably Kent). 



Inoceuamts Tur.EKcur.ATi's, sp. nov. Plato lAY, fig. 8. Text-fig. -59. 

1882. Inoceramus c.\rdissoides, II. Srlii-i'uh'r. Zc-itxlir. d. deulscli. geol. 

Gesellsch., vol. xxxiv, p. 271, 
pi. xvi, fig. 1 (Non Goldfuss). 

Besi-rijifidii. — Shell very inequilateral, ol)li(|ue, niucli higliei- than long; dorsal 
part moderately convex, ventral part only slightly convex. Umbones relatively 
small, nearly terminal. Antero-doi'sal ai-ea flattened, nearly smooth. A rounded 
depression, separated from the posterior Aving-like part, passes from the umbo to 
the postero-ventral extremity. Hinge-line forms less than a right angle with the 
anterior margin. 

Ornamentation consists of numci'ous concentric ribs which, at a short distance 
from the umbo, are crossed by radial furrows, so that the ribs appear then 
to consist of rows of tubercles ; on the sides of the shell the radial furrows, 
and conserpiently also the tubercles, are less distinct than on the middle of 
the shell. 

AJfiiiities. — This species is allied to /. Inhntiis and /. cardissoides, but differs in 
the greater development of the radial ribs, which give rise to a tuberculate type 
of ornamentation ; also the stronger concentric ribs which occur in I. ca)xlissoides 
are small or altogether wanting. The English specimens agree fairly closely with 
the example figured by Schroder as 7. cdrdissoidi's. 

Tijpc — In Dr. Rowe's Collection. 

Distrilmtioii. — Upper Chalk (zone of Actiiwcamax (jiiadratns) of Brighton, and 
Sewerby (Yorkshire). 



INOCERAMUS. 



303 



■A. •«*»»> 





Fiii '<'^ — /iicir.r.imus (iifcfivii/.idis, sp. nov. Zono of Aclinocamax qHmlralus of Sewerby, Yorkshire. 
Dr. A. W. Kowe's Collection. Port of rij^ht valve. Natural size. 



304 CRETACEOUS LAiMELLIBRANCHIA. 



Inocekamus UNDULATO-rncATiis, lujiiicr, 1852. Text-figs. 60, 01. 

1852. Inoceramus undulato-plicatus, F. llinner. KreidcliilJ. v. Texas, p. i>9, 

pi. vii, fig. 1. 
1865. — DiGiTATUS, F. A. Ei'niier. Palaontographifa, vol. xiii, p. 196, 

pi. xxxii, fig. 6. 
1873. — — F. Schmidt. Mem. Acad. Imp. Sci. de St. 

Pctersl)., ser. 7, vol. xix, no. 3, 

p. 25 (partim), pi. v, figs. 10, 11 ; 

pi. vi, fig. 1, 2, 4, 6, 7 ; pi. vii ; 

pi. viii, figs. 9 — 15. 

1877. — • UNDULATO-PLICATUS, C. Scltliiter. Paleeontographica, vol. 

xxiv, p. 270, pi. xxxviii, 
fig. 1. 

1878. — — C. Barrois. Ann. Soe. gcol. du Nord, 

vol. V, p. 475. 
1894. — DioiTATUs, A'. Jiiiiho. Palaeont. Abhaudl., vol. vi, p. 43, 

pi. viii, figs. 8—10. 
1899. — ScHMiDTi, B. Michael. Jahrb. d. k. preuss. geol. Laudesanst. 

fiirl898, vol. xix, p. 162, figs. 1—4. 

Descyiptloii. — Shell ovate, much higher than long, very inequilateral ; the early 
part of the shell of small or moderate convexity, the later part only slightly convex 
or nearly flat. Hinge-line forming more than a right angle with the anterior 
margin. Umbones terminal, small, curved anteriorl}'. 

Ornamentation consists of concentric and radial ribs ; the former are more 
distinct on the early part of the shell, the latter on the later part. The radial ribs 
curve outwards from a line between the umljo and the postero-ventral extremity ; 
they have rounded summits, and arc separated by broad shallow interspaces ; a 
tubercle or rounded elevation may l)e developed where the concentric ribs cross 
the radial ribs. 

A[fiiii,fiet>. — This species is closely allied to J. Jiijitatns, Schliiter {nun 
Sowerby) . 

The fact that in some specimens the early part of the shell is ornamented with 
concentric folds only, and the radial ril)s appear on the later parts, suggests 
that this species has been derived from one with concentric folds only, in a 
manner similar to that in which 1. sulcatus has arisen from /. coiicentricus (see p. 
2G8) ; the specimens at present available, however, do not enable us to trace the 
origin of I. undulato-])licatiis, but it seems probable that it has descended from a 
flat variety of I. inconstans. 

Forms from Vancouver Island with a similar type of ornamentation have been 



INOCEEAMUS. 



305 



referred to /. )iu<hil<do-plicafiis l)y Whitoavcs,' but White- doiil)ts the correctness 
of the identification. 1. (lit'evsufi, Stoliczka,'' is anotlier allied form. 

Michael does not accept Schmidt's and Schli'iter's identification of the 
specimens from Saghalien and North Germany with Rnmer's 7. VHthdato-plicatus, 
but regards them as belonging to a distinct species for which he proposes the 
name I. Schniidti. He, howe\'er, regards /. (h'lyri^Hs, Stolic/.ka, as an example of 



F.u. (il. 



Fig. fill. 




Fig. go. — Inoceramus undulato-plieatus, Kiiiii. Sonoiiian. UaMuu. liritisli MiLsciiiii, Xu. L17371. Flint 

Ciist of part of right valve. Natural size. 

Fig. 61. — Inoceramus nndutnto-pUcnius, Eiim. Senonian. llaMcm. liritisli Museum, No, 1,1736'.'. x I. 

this species, consequently it \v;is uniieecssary to inti'oduce a new name. The 
English specimens show a good deal of variation, and after comparing them with 
Rcimer's and other figures I do not feel able to accept Michael's view. 

jTv/jJC. — From the Chalk of Te.\as. 

Disfribitfiioi. — Senonian of TTaldon. 



• ' Geol. Siirv. Canada, Mesoz. Fosf.,' vol. i (1879), p. 168, pi. xx, fig. 2, and /. digitatiis (ibid., 
1903). p. 395 ; also ' Trans. Roy. Soc. Canada,' ser. 2. vol. i (189.5), p. 121. 
« 'Bull. U. S. Geol. Surv..' no. 51 (1889), p. 37. 
' ' PaloBont. lodica, Civt. Fauna S. India,' vol. iii (1871), p. 407, pi. xxvii, fiij. (J. 



306 



CRKT A ( ' HOC S LA^IE [ J JBE AXC ITTA. 



i 




Fig. 



Ii2 — Jnocei-nnius umluhito-pUrntiis var. diqitatus. SchUit. Z..no of 3/io-asf.T ,-oi-an,j<il,nnn. Suowclown 
Ci)llii>ry Shalt. Noniujjton, near Diivcr. British Museum, N". LliosU (.liscoverea and presented by 
Dr. Malcolm Burr). Cast of part of left valve, x J. 



V,' 



IXOCE RAMUS. 307 



Inoceramvs VKDii.ATo-i'i.K Alls ntv. iMciTAns, Srliliitrr, 1877. Text-fig. G2. 

1873. Inoceramus dioitatus, F. Sclmidt. Mini. Acad. Imp. Sci. de St. Pt'tersb., 

sei'. 7, vol. xi.\, no. 3, p. 2.5 {2iartim), 
]il. vi, fi^-.s. 3, 5. 

1877. — — C. Schliiter. Palseoutograpljica, vol. .xxiv, p. 267, 

jil. xx.wi. 

1878. — — C. Barniis. Ann. Soc. fjcul. du Nord, vol. v, 

p. 475. 
1902. — — A. Wdlli'iiiinni. Li'meburg. Kreide (Abliandl. d. 

k. preuss. geol. Landesanst., 
N.K., 37), p. 70. 

Revuirl-s. — As was pointtMl out liy Scliliiter, this form is very closely allied to, and 
perhaps not separable from, /. n whilato-plicatii s ; it differs from the latter mainly 
in that the posterior ribs are strony-er and fewer in nunilier than the anterior ribs, 
but the early parts of the shell are very similar in the two forms. Until more 
specimens have been obtained the exact relationships of the two forms cannot be 
determined, and for the present it seems best to r(>o-ard /. digitittuH of Schliitcr 
{non Sowerby) as a variety of I. nndiihitu-jtUcatiis. 

Distribafion. — Zone of Micratttev cor-anr/niiiitm of Charlton, Snowdown Colliery 
Hliaft, Xonington near Dover, I'reston near Faversham, and Salisbury. Zone of 
Actinocamax quailratun of Salisbury. 



Inoceuaml's L\si\\ivKi, Furli-iitson, 1819. Plate Lll, figs. 1- — G; Plate LIII, figs. 

1—7. Text-figs. 63—85. 

17(i8. OsTREOPiNNiTES, J. E. I. Walch. Naturtfesc-liiclite d. Verstelu., vol. ii, 

p. 142, pi. Di*», figs. 1—5. 
1819. Inoceramus Lamarckii, J. Parkinson. Trans. Geol. Soc, ser. 1, vol. v, 

p. .5.5, pi. i, fig. 3. 
1822. — CuviEKi, J. ::>oirt'rhi/. Trans. Linn. Soc, vol. xiii, p. 453, 

Jll. XXV. 

— — Lamarckii, G. Mantell. Foss. S. Downs, p. 214, pi. xxvii, 

fig. 1. 

— — CnviERi, Mantell. Ibid., p. 213, pi. xxvii, fig. 4, pi. xxviii, 

figs. 1, 4. 

— — IIkononiakti, ^fantell. Ibid , p. 214, pi. xxvii, fig. 8. 

— — Websteki, MiiiilfH. Ibid., p. 21»), pi. xxvii, fig. 2. 

— — vvDVLJiTVS, Mantell. Ibid., p. 217, jd. .xxvii, fig. 6. 

— — LATUs, Mtnil-ll. Ibid., p. 21(), pi. xxvii, fig. 10. 

— Catillus Cuvikki. .1. ISronyniart. lu Cuvier's Ossemens Foss., vol. ii, 

p. 601, pi. iv., fig. 10. 



308 CRETACKOUS LAMELLIBRAXCHIA. 

1823. Inuckramus Cuvieri, J . de C. Soverlnj. Miii. Conch., vol. v, p. 59, \'\. 

ceocxli, fi^'. 1. 

— — Brongniarti, Suicedii. Ibid., vol. v, ]\. GO, pi. ccxcxli, figs. 

2. 3. 

1836. — Lasiarckii, A. Goldfuss. Petref. Germ., vol. ii., p. 11-i, ]>1. 

fxi, fig. "2. 

— — CuviEiti, (Jultl/iiss. Ibid., vol. ii, p. Ill-, pi. ixi, fig. 1. 

— — Brongniaeti, Goldfues. Ibid., vol. ii, p. 115, pi. cxi, fig. 3. 

— — STRIATUS, Gold/tiss. Ibid., p. 115, pi. cxii, fig. 2. 

183". Catillus lamarcki, F. BiijanVm. Mrin. Soc. gi'ol. de France, vol. ii, 

p. 225. 

1837. — Cuvieri, DnjanJin. Iliid., vul. ii, p. 225. 

— Inoceramus Brongniarti, IF. Hisiiiijer. Letliaea Suecica, p. 56, pi. xvii, 

fig. 11. 

— — CvYiERi, Hii'iiKjer. Ibi '., p. 5li, pi. xvii, fig. 10. 

18-il. — Lamxrcku, F. A. Riimer. Die Versteiu. d. uord - dentsch. 

Kreidegeb., p. 62. 

— — CuviEiii, Ri'imer. Ibid., p. 62. 

— — Brongniarti, iio/Her. Ibid., p. 61. 

? — — TJNDULATUS, Riiiiier. Ibid., p. 63, pi. viii, fig. 12. 

1846. — Cv\iBRi, A. E. Reitss. DieVersteiu.derbiihiu. Kreideformat., 

pt. 2, p. 25. 

— — Brongniarti, Reuse. Ibid., pt. 2, p. 24. 

y — — Cuvieri, A. Leymerie. Statist, gcol. niin. de I'Aube, Atlas, 

pi. iv, fig. 7. 
— ■ — ANNULATUS, Leymerie. Ibid., pi. iv, fig. 4. 

— — Cuvieri, A. d'Orbigny. Pal. Franc. Terr. Crc't., vol. iii, 

p. 520. 
1850. — Brongniarti, H. 5. GeMi^^z. Das Quadersandst.oder Kreide- 

geb. iu DeutscLland, p. 172. 
r' — — Cuvieri, A. d'Orhigiiy. Prudr. de Pal., vol. ii, p. 250. 

1850. • — — R. Kner. Kreidemerg. v. Lemberg (Haidinger's 

Naturwiss. Abliandl., vol. iii, pt. 2), 
p. 28. 
1854. — Lamarckii, /. Monts. Cat. Brit. Foss., ed. 2, p. 169. 

— — Cuvieri, 3Iorris. Ibid., p. 169 (parlim'). 

— — Brongniartii, Morris. Ibid., p. 169. 

— — UNDULATUS, Morris. Ibid., p. 170. 

— - — Websterii, Morris. Ibid., p. 170. 

1863. — Cuvieri, A. v. Siromlieck. Zeitsclir. d. deutscli. geol. Gesell- 

scli., vol. XV, p. 124. 

— — Brongniarti, Siromleclc. Ibid., vol. xv, p. 121. 

— — — R. Drescher. Ibid., vol. xv, p. 352. 

?1869. — Damarki, E. Favre. Moll. Foss. de la Craie de Lemberg, 

p. 134. 
1870. Inoceramus Brongniarti, F. Ri'nner. Geol. v. Oberscbles., p. 316, I'l. 

xxxiv. fig. 13. 



IXOCERAMUS. 309 

1872. Inoceeamus Bkongniarti, Jf. -B. 6'e>i«i7z. Das Elbthalgeb. in Sachsen 

(PalBeontogrnphica, vol. xx, 
pt. 2), p. 48, pi. xi, figs. 
3—10, pi. xiii, fig. 3. 
P _ — CuviERi, Geiiiltz. Ibid., p. 48 (partim), pi. xiii, fig. 8. 

Ig73 — Brongniakti, Get/iite. Neues Jalul). fiir Miti., etc., p. 10. 

s- — CuviERi, Geiiiih. Ibid., p. 15. 

p — — Lamarcki, Gelnitz. Ibid., p. 18. 

i* 1875. — LATUS, G. Drcorq. Assoc. Frauc. Avauc. Sci. (Lille, 1874), 

p. 369. 
J877. — CuviERi, C. ScJdiiter. Palseontographica, vol. xxiv, p. 266. 

— Brongniarti, C. SclMter. Ibid., vol. xxiv, p. 263. 

_ _ — A. Fritsch. Stud, ill! Gebiete der biihm. Kreide- 

format.,ii, Weisseuberg. u. Mal- 
nitz. Schicht., p. 130, fig. 111. 
187g_ ._ — G.Behrens. Zeitschr. d. deutscL. gee). Gesellsch., 

vol. XXX, p. 256. 
p _ _ UNDULATUS, C. Bavrois. Auu. See. gcol. du Nord, vol. v, 

p. 407. 

1881. (Mytilites) problematicds, J?. Etheridgr, iu Peuuing and 

Julies-Browne, Geol. Cam- 
bridge, p. 143, pi. iii, figs. 
9, 10, 11. 
p 1883. — Brongniarti, A. Frilsch. Slud. im Gebiete der bOhm. Krei- 

deformat., iii Iserschicht., p. 110, 
fig. 80. 
1888. — CuviERi, 4. PeroH. Hist. Terr. Craie S.E. Bassin Anglo- 

Parisien, p. 156. 

— Brongniarti, Peron. Ibid., p. 157. 

— rNDULATUS, Peron. Ibid., p. 15/. 

P1889. — CuviERi, ^. Pri7«c/(. Stud, im Gebinte der biilim. Kreide- 

format., iv, Teplitz. Scliicht., p. 82, 
fig. 74. 
p _ Brongniarti, Fritsch. Ibid., p. 81, fig. 72. 

1892. — CuviERi, E. Stulley. Die Kreide Sebleswig-Holsteins (Mit- 

theil. a. d. miu. lustitut Kiel, vol. i.), 
p. 241. 

1893. _ Brongniarti, E. Michael. Zeitschr. d. deutscb. geol. Gesell- 

sch., vol. xlv, p. 242. 
1897. _ striatus, H. Woods. Quart. Jouru. Geol. Soc, vol. liii, p. 381, 

pi. xxvii, fig. 13. 
_ _ CuviERi, B. Lconhanh Pateontographica, vol, xliv, p. 49. 

_ — Beononiakti, Leonhard. Ibid., vol. xliv, p. 47. 

1899 _ _ J. Simionescu. Fauna Cret. Super. Urmos, 

p. 27. 
? _ _ CuviEEi, SimioiiescH. Ibid., p. 27, pi. ii, figs. 8, 9. 

P1901 — a£f. CuviERi, H. ImJceller. Paloeontographica, vol. xlviii. 

p. 34. 

41 



310 CRETACEOUS LAMELLIBRANCHIA. 

llMll. Inoceramus CuviERi, J^. (S7((n»i. Jalnb. d. k, jireuss. g-eol. Landesanst., 

fur 1900, vol. xxi, p. 92, pi. x, fig. 1. 
in02. • — — A. WuJIemann. Liiiiebuif,'. Kreide (Abhandl. d. k. 

preuss. gc'ol. Landesanst., n.f., 37), 

p. 67. 

— — Brongniarti, Wollemann. Ibid., p. G6. 

1903. — — W. Petmscheck. Jahrb. d. k. geol. Kfichsanst., 

vol. liii, p. 161. 

— — CuviERi, PefraschecJc. Ibid., p. 162. 

1904. — i^ATVs, E. T. Ncwti n and A. J. Juices-Browne. In Jukes- 

Browne, Cret. Rocks of Britain, vol. iii, 
p. 448 (partim). 

— — COBDIFORMIS, C ^ ('*•(»;/'"• Boll. Soc. geol. Italiana, vol. xxiii, 

p. 189, pi. iv, figs. 6—9. 

1908. — Ctivieri, a. Sfojanoff. Ann. gi'ol. niin. Russie, vol. x, p. 121. 

1909. — — J.Nowal: Bull. Internat. Acad. Sci. Cracovie, p. 875. 
1911. — LATUS, W. Ro/jala. Ibid. (1911), p. 172, pi. iv, figs. 9, 10. 

— — KoEGLERi, H. Andert. Inocerameu d. Kreibitz-Zittauer Sand- 

steingeb., p. 57, pi. v, fig. 6, pi. i, fig. 6. 

Nou 1827. — CvYiERi, S. NHsson. Petrific. Sueeana, p. 19. 

? — — Catillus Brongniarti, Nthsoii. Ibid., p. 19. 

— 1832. Inoceeamus undulatus, C. H. v. Zieten. Versteiu. Wiirttembergs, p. 96, 

pi. Ixxii, fig. 7. 

— 1846. — Lamarckii, A. iVOrhiijtiy. Pal. Fian^. Terr. Cri't., vol. iii, 

p. 518, pi. ccccxii, figs. 1 — 3. 
? — 1847. — CcviERi, J. JI/»7/er. Petref. der Aaclien. Kreidef., pt. 1, p. 31. 

? — — — Brongniarti, MiiUer. Ibid., pt. 1, p. 30. 

— 1850. — Lamarckii, /. dc C. IScverli!/. In F. Dixon, Geol. Sussex, 

p. 365(p.385,ed.2),pl.xxviii, 
fig. 29 (= J. inconstans). 

— 1866. — liA'M AUCKi, K. A. Z iff el. Bivalv. d. Gosaugeb. (Denkschr. d. k. 

Akad. d. Wissensch. Wien, Math.- 
nat. CI., vol. xxiv), pt. 2, p. 99 [23], 
pi. XV, fig. 6. 

— 1872. — — H. B. GeinHz. Das Elbtlialgeb. in Sachseu (Pal- 

ffioutograpliica, vol. xx, pt. 2), 
p. 50, pi. xiv, fig. 1 (fig. 4 = 
gaxonicvs, Peti'ascheck) . 

— — — CuviERi, Geinitz. Ibid., p. 48, pi. xiii, figs. 6, 7. 

?— 1872—3. — STRiAivB, Geinifz. Ibid., pt. 1, p. 210, pi. xlvi, figs. 9— 13 ; 

pt. 2, p. 41, pi. xiii, figs. 1, 2, 9, 10. 

— 1899. — undulatus, J. Simionesni. Fauna Cret. super. Uruios, p. 26, 

pi. iii, fig. 2. 

— 1904. — Beongniaetii, C yli7a(/A(. Boll. Soc. geol. Italiana, vol. xxiii, 

p. 192, pi. iv, figs. 3 — 5. 

— 1911. — CuviEEi, H. Andirt. Inoceramen d. Kreibitz-Zittauer Sand- 

steingeb., p. 44, pi. ii, fig. 2. 



INOCERAMUS. 311 

Dctirriptiu)i. — Shell inequivalve, very inecmilateral, of slight, moderate or 
considerable convexit}-, sometimes inflated. Height greater than length. Hinge- 
line of variable length in proportion to the height of the shell, forming more than 
a right-angle with the anterior margin. Umbones terminal, cnrved inwards and 
more or less forwards ; the left umbo more prominent than the right. Anterior 
marginal part of valves flattened, more or less nearly perpendicular to the plane 
of the valves, either limited by a sharp edge from the flanks or without a definite 
boundary. Anterior ear developed in some flat varieties. 

The concentric folds may be absent, indistinct, or moderately or strongly 
developed, with the dorsal and ventral slopes similar or with the ventral slope 
steeper than the dorsal. Usually the folds are regular, but are not continued on 
to the posterior ear. The curvature of the folds is often nearly symmetrical ; 
its convexity on the convex and on some of the flat forms is small, but is greater 
on the flat forms with a relatively short hinge. The growth-lines are distinct 
and variable in number, and are sinuous where they pass on to the posterior ear. 

RemarJiS. — The forms included in this species show a great amount of 
variation, and seem in that respect comparable with some species of Mlcranfer and 
Echinoconis. Several of the varieties have been described as distinct species, but 
the stud)' of a large series of specimens has shown so many intermediate forms 
that one can only regard the varieties as modifications of a very plastic species. 
The features in which variation is most marked are the convexity of the valves, 
the number, strength, and curvature of the concentric folds, the distance between 
the growth-lines, the size and distinctness of the posterior ear, and the height of 
the shell. 

Some forms of this species are only slightly convex (Plate LIII, fig. 7, Text- 
figs. 73 — 83), so that in large specimens considerable portions of the shell 
approach flatness. In other forms the valves are moderately or considerably 
convex, and sometimes inflated (Plate LII, figs. 4, 5, Text-figs. G3 — 68). The 
amount of convexity may remain nearly uniform throughout the growth of the 
shell, or the earlier part may be only slightly convex and the later part very 
convex — in such cases the early part resembles the adult shell of the large flat 
varieties (Figs, (il, Go). The two valves may be of nearly ecjual convexity (Plate 
LII, fig. 5), or the left valve may be very convex whilst the right valve is only 
slightly convex (Plate LII, fig. G). 

The concentric folds vary in strength, niunber, form, curvature and regularity. 
In the majority of cases the folds are prominent and form strong ridges (Figs. (SS, 
G9, 7S, 82, 84-), but they may become only gentle undulations (Figs. 74, 77, 81), 
and are sometimes indistinct or absent (Figs. 73, 7-J, 7G, 71>)- The dorsal and 
ventral surfaces of the folds may slope equalh', or the ventral slope may be 
steeper tiiaii the dorsal, giving a step-like appearance. The crest of the fold is 



312 



CRETACEOrS LA:\IETJJBRAX('H1A. 





Fig. 63. — Inoceramiis ifiHiariAi, Park. The type. Uppor Chalk (probably zouo of Jllicriis/cr cor-a>ig«iHKin), 
near Dover. British Museum, No. L9S0] . Left valve and dorsal view. Part of the posterior ear is 
concealed by flint. Natural size. 




Fig. 6!-.— /iioi-craoiiis Lamarcl:i, Park, Anterior view of specimen shown in Fisj. Go. x 



IXOCERAMUS. 



313 



Fio. 05 



Fig. 67 




Fig. Go. — Iiioceramiis Lamarcii, Park. Upper Clialk (probably zone of Holaster planum), Swaffliam, Norfolk. 
Norwich Museum, No. 3354. Ki^ht valve. x i. 

Fig. 67. — Iiirn-enimm Lamarcld, Park. Upper Chalk (zone of Holaster 2>lanii.\), Newmarket. Sedgwick 
Museum, Cambridge. Kight valve. Natural size. 





Fig. Tfi. — Inorci-oiiiii.s I.iniKinki, I'ark. The original of /. Lnmarcki, Mantell, 'Fobs. S. Downs,' p. 214, 
pi. xxvii, fig. 1. Middle Chalk (priibal>ly zone of Terebratiilimi latn), near Lewes (probably Mailing), 
liritish Museum, No. 4753. Kight valve. Natural size. 



114 



f'T^ETACEOUS LAMELLIBRANCHIA. 





Fio. 68. — Inuceramns Lamiurki, I'ark. The type of /. Bi-oiigniarti, Mautell, ' Foss. S. Downs,' p. 214, 
pi. xxvii, fi^. 8. Prom Lewes or Brighton, probably zone of Micrasler cor-anguintim. British Museum, 
No. 4751. Left valve anil dorsal view. Natui-al size. 




Fio. 69. — Inoceramtis Lamarcki, I'ark. The original of /. Cuvieri, Mantell, ' P'oss. S. Downs,' p. 21.3, 
pi. xxviii, fig. 4. Zone of Mi>ni.v(i'r cor-antjiiinum, Southerani. British Museum, No. L22094. x |. 



INOCERAMUS. 



315 



KiQ. 70. 



Fi. 





Fig. 70. — Inoceramus Lamarchi, Park. The original of I. Bronr/nUnti, Suvvfrby, ' Min. Conch.,' vol. v, 

p. 60, pi. ccccxli, &g. 2. Chalk. Locality and horizon unknown. British Museum, No. 13265. 

Right valve. Natural size. 
Pig. 71. — /noceramws Lamarcki var. IVebsteri, Mant. The type of /. JJ'ebsteri, Mantell, ' Foss. S. Downs,' 

p. 216, pi. xxvii, fig. 2. Upper Chalk (probably zone ot Micraster cor-testudinarium) , South Street, 

Lewes. British Museum, No. 4-7o9. Left valve. Natural size. 

Fig. 73. 



Fio. 72. 





y 




.jmt 




Via. 72. — Inoceramus Lamarcki var. Websteri, Mant. Upper Chalk, Swaffhaui, Norfolk. Norwich Museum, 

No. 32!»S. Left valve and anterior view. Natural size. 
Fia. 73. — Inoceramus Lamarcki var. Cuvieri. Sow. The type of inoceramus Cuvieri, Sowerby, 'Trans. Linn. 

Soc.,' vol. xiii (1822), p. 453, pi. xxv, figs. 2, 3, and 'Min. Conch.,' vol. v (1H23), p. 5!l, pi. ccccxli, fig. 1. 

Middle Chalk (zone of Terebralulina lata), Koyston. British Museum, No. -13204. Left valve. 

Natural size. 



316 



CRETACEOUS LAMELLIBRANCHIA. 



usually roimded, l)ut in one variety {WtJisteri, Mantell, Plate LTII, figs. 1, 2, 
Text-figs. 71, 72) it possesses a sharp edge. When the folds are absent the 
growth-rings become more regular. The curvature of the folds is usually small 
in the more convex S})ecimens, but often greater in the less convex forms. The 
curvature is often nearly symmetrical, but when the posterior ear is indistinctly 
limited it tends to become unsymmetrical. 

The degree of development of the posterior ear varies considerably. In some 
forms it is only indistinctly limited (Plate LIII, fig. 7, Text-fig. (38), and tlien the 



{' 




Fig. 74. — Inoceramus Lamareki var. Ciivieri, Sow. Upper Chalk (zone of Micraster cor-anguinum). Camp 
Hill, near Salisbury. Dr. Blackuioro's Collection. Portion of a large left valve ; posterior and ventral 
parts missing, x |. 

folds and growth-lines are continued with but little alteration in curvature on to 
the ear. In other cases the ear is larger and more or less distinctly limited from 
the rest of the valve (Plate LII, fig. 4, Text-figs. 03, (35, 66, 79, 81, 82) ; in such 
cases the folds and growth-lines bend inwards at the limit, and the umbonal part 
of the valve is often narrower and more acute. In a few large, flat forms, an 
anterior ear is developed (Fig. 74). 

The anterior flattened area varies in size and in the distinctness of its 
boundary. It may be nearly perpendicular to the plane between the valves 
(Fig. 81), or may be slightly concave (Figs. G3, 66, 79), or slope outwards (Figs. 



INOCERA.AirS. 



31 : 



74; 79). Ill some varieties the iii-e;i forms a sliai'p edge -witli tlie sides of the 
valve (Fig. 81), in otliers tlie l)(>midar\' is curved and tlie limit of the area is 
indistinct (Fig. 85). 

In the type of /. Lamarclci, Parkinson (Fig. 03), the shell is inflated, and the 
posterior ear well developed and sharply limited. In forms like T. Brour/niarfi 
Sowerby (Fig. 70, PI. LII, tig. 4), the posterior ear is also well developed, but 





^» 



^/> 



^ 




Fig. 75. — Inoceramiis Liimarrki v.ar. Cuvieri, Sow. Upper Chalk, Southevam, l/owos. Biightou Museuin, 
No. 340. Poi-tion of :i Ifft valve ivseiiibliiijf tho type of I. latus, Mant. x |. 

not so sharply limited as in the type of I. Lamarcki. Mantell's /. Lamarclci 
(Fig. 66) is similar to /. Bronfjniarti, Sowerby, but has less prominent folds and 
a more concave anterior border. /. Brougniarfl, Sowerby, passes gradually into 
forms like the type of /. Bi-ninjiiiarfl, Mantell (Fig. 68), in which the limit of the 
posterior ear is somewhat indistinct. Other varieties possess similar strong folds 
but, have less convex* valves (as in /. Cuvieri, Mantell, Figs. 69, 84), and these 

' lu some cases the smaller convexity may be due to pressure which gradually changed the 
shape of the shell. When no fractures are seen, flattening appears to be indicated in some cases by 
the growth-lines cutting the folds obliquely. 

42 



ns 



CRETACEOUS LAMEi.LlHRANCllJ A. 



pass into forms with i.ulistinct folds like the tvpe of /. Curu'ri, Sow^rhy (Eig. 
7:}), iiiul in some cases tht- fohls disappear altogetlier. 




'k 







Fig. ^G.-Inocera,nus Lamarcki va.. CuvicH Sow. The typeof I^'^^!'^^^^'^^'''^^'^^- 
p. 216, pi. xxvii, &s- 10- Uppci' Chalk, near Brighton. Britisli MusLum, s\o. 
Natural size. 

I. Wehster!, Mantell (Figs. 71, 72), Las the posteriov ear fairly well developed, 
but not distinctly limited, and resembles /. Urongniarti of Planted ; it is 
characterised l,v the thinness of the shell and the sharp ridge-Lko folds, but forms 



INOCK RAMUS. 



319 



mteniiLMliate between tliis type and those witli runndetl folds occur. It may 
be convenient to adopt lor this variety the name /. TjH tmi rrJ:'i ww. ]V('hsfi'ri. It 
appears to occur mainly in the zone of Micraster cor-testadiimrium. 

]. tniiliilnfns, ]\[antell (PI. LIII, fio^. 3), resembles small forms of I. BroiKjinarll, 
Sowei'l)y, but the folds are much smaller, more numerous, and less conspicuous, 



an 



d f 



le shell IS thicker tlian usual. 



i. 







Fig. 77. — Iiiocohhiks Lmiinrchi var. Citvieri, Sow. U|>|)( r Chalk (zone of Holiisler ji/miiis), Si\:ifTli:iiii. 
Niiil'ulk. Norwich Mtiscuiii. I.oft valve. x J. 

Some small forms (IM. Id 1 1, figs. 4— G), found in the .Middle Chalk and in 

the zone of Iluldstcr jihiniis, which may 1k> named /. Ldinnrrkl var. apicdlix,^ have 

neai-ly eipial valves, more prominent ami more distinctly incurved umbones, with 

the folds indistinct or al)sent, but these forms pass into others with distinct folds. 

In some of these small forms the umbo is curved anteriorly (Plate LIII, tiu^. -I). 

' An I'Xiimiik- of tlii.s I'l-am the Chalk Rock was figured in tlie ' Quart. Ji>urn. Geol. Soc," vol. liii 
(18St7), p. 381, pi. .\xvii. fi-. 1:;. 



320 



CllETxVCEOUS LAMELLlBliA.XCUIA. 



/. hitns, ^Mantel] (Fig. 76) is a large, slightly convex form in wliicli the folds 
have almost disappeared. In the type (Fig. 7')) the postero-dor.'^al part of 
the valve is missing, so that in ]\ranteirs figure the umbonal part of the valve 
appears to be more acute than it really is (compare Fig. 75). 

T. Guvieri, Sowerby (Fig. 73) is only slightly convex, with indistinct folds, and 
is often of large size. The angle formed by the antei'ioi- margin and \\\v hinge- 
line is rather larger than usual, and a!i anterior ear niav be developed ; other forms 




Via. 78.— /iiocccamns Lamarcki var. Cuvieri, Sow. Upper Chalk, Lewes. Sedgwick Musouin, CambiiJfjo. 

Eiglit valve. Natural size. 

are similar (Fig. 7'.'), but have a smaller angle between the anterior margin and 
the hinge, and these pass into forms with more distinct and eventually with 
strong folds (Figs. 77, 78, 82). The varieties similar in form to Sowerby's type, 
l)ut with or withont folds, may be termed /. Lamarcld var. Cuvieri (Plate LIII, 
tig. 7, Text-figs. 73 — 84). The hinge in large specimens of this variety (Fig. 80) 
is of great thickness, and portions of it are often founil separately. It is thickest 
near the undx), and l)ecomes thinner towards the posterior end. The ligament 
pits ai-e numerous, shallow, and two, three, or more times highei' than long, 



INOCERAMUS. 



321 




i 









Fio. 79. — Inoccramus Lamorchi var. Cuvieri, Sow. Zone of Holnster planus. Borstal. Jlr. Dibley's Collec- 
tion. Ei^ht valve and anterior view, x 5. 9 




Firi. SO. — Iiioeeramas Lamareki var. Cuvieri, Sow. Zone of Terehratnlinn /<i/ii.Royston. SeJ>jwiek Mu.seuni, 
Cambridfje. Portion of left liinfje. Natuml size. 



,'322 



CKKTACKOL'S LA.M KU J I'.iiAXCII I A. 



ivacliiiiL;- tlicir iniixiimmi lici^lit not far fVdin the iiiiiho. 'I'lio variety Chiricri 
ranges from tlie zone oF Trrcl'i-iihiliiin lata to tlie zone of Micrai<ter cor-anguinum. 

T. M(i)itdli, de ]\Ierce_v,' from the zone of Min-'isler cor-iinf/ninum, appears to 
])(■ a large form of /. Lauiarchi var. CiLcleri, in wliieli an anterior ear is developed; 
it is similar to a specimen (Fig. 74-) obtained i)y Dr. Blackmore from the zone of 
Mirrtisifpf (■iij--iiii)iiiiiinn/ of Camp liill neai- Salislmrv. 







1..__-9 



^^^-: 



y 



Kk; si. — Iiiorpi-niiiiK l,,iiiH(irli vnr, C'lit'icri, Sow. Z.>no of Tci-fhi-iilalinii lutii, Bluo Bi-ll Hill, liui-liam. 
Mr. Dililcy's Cdllctti.Mi. Left Viilvc with imstcriur part luissiii!,' ; antcrim- view of the same valve. x J. 

7. /ii-i-i-i)st,ifiis. .Midler- ('especially tlie example tignred liy IV'traseheek''), seems 
to be closelv allied to f. I,ii iiKirfl/i xar. II ('/(.s7r/-/. 

Ti/pc!^. — /. I]iiinitri-l-i, I'ai'kinson ( l''ig. (>:')), IVom near Dover ( [iroKalily /.one of 

' • Mem. 8ne. Linn. Nonl .Ir la Knuiei',' vol. iv (1877), p. o-Jt. [ils. i. li. Barrel-. ' .\.un. Sne. 
^■eol. Nunl," v.il. vi (187lt). 1'. 4.')t. pi. iv. 

- ' Jalnli. (1. k. pivuss. <,'('(.!. LiUKlo^aiist. u. Bi'ri,'aka<l. fiir 1887' (1888), p. 413, pi. xvii, fig. 3. 

= • Jaliili. il. k. k. t:eoi. Reielisanst.,' vol. hi (IHUC), p. Iti3, fiij. 2. Also I. Glatziic ami /. Klelin, 
,\n(lci-t. • Iiioeeraincn .1. Kreil.it/,-Zitlaufr Samlstciiigcl).' (lUIl ), ].p. ts, r,->. pi. i, fig. 3, pi. ii, tig. 8. 



iX()ri-:u.\:\irs. 



323 



Micra.'iter ciir-auijiiliunii) ; in the Ui'iti.-li Afuscuiii, Xo. I/JSUJ. This siieciineii was 
first I'ccogiiiscd as the original of Parkinson's figure hv Mr. (". D. Sherboni. 



/ 




,^' 



/ 



Fio. SJ.— //locfi-rtiiiKs LoDuiixli Viir. C'«i-i«M-i, Sow. Chalk; Imwlity ami horizon unknown. BritUli Museum, 

No. LaSiW'J. Kijjlit valve, x {. 

]. .C'li fieri, Sowerliy (Fig. 7o), from the Mi(hlK> Chalk of Royston (zone of 
Terchratnliaa lata); in thi" British Museum, Xo. 4o:2(Jl-. 

/. Lumarrhi, >faiite]l (Fig. 00), from the ^Middle Clialk near Lewes (probably 
from dialling, zone of TvrcbmiaUna lata) ; in tlie British Museum, Xo. 47-Jo. 



324 



CRETACEOUS LAIM KLLI BRANCJ 1 1 A. 



/. Cuvieri, Mantell (Figs. 69, 84), both from the zone of Mirrnster cor-ami^ihitnii 
of Soutlierani ; in the British Museum, Nos. 5845, L22(V,»4. 

I. Broii'jniiirfi, Mantell (Fig. 08), from Lewes or Brighton (probahly zone of 
Micraster cor-aiu/niiinw) ; in the British Museum, Xo. 1751. 




I'lO. S3. — Auterior view of specimen showu iu Fig. 82. x }. 



/. Wehsteri, Mantell (Fig. 71), from Houth Street [= Southeram], Lewes 
(pi'obablj zone of Micraster cor-tcdndimirUtm) ; in the British Museum, No. 4759. 

/. uadalatus, Mantell (Plate LIII, fig. o), from Southeram, Lewes (probably 
zone of HiAaster jylfimts) ; in the British Museum, No. 4767. 



IXOCERA.MUS. 



325 




FiCi. SI. — Innrer'unns LumarH-i var. Ciivieri, Sow. Tlie oriu-inal of /. Cuvii'ri. Maiiti41, ' Foss. S. Downs,' j). 213, 
pi. .\xviii, tii^. 1. Zone of ^Ji'-Tfry^er coj'-a/(^uintu» of Soiitli'Tain. JJriti.sh ^lustniin, Xo. 5845. x \. 





Fio. 85.— I/iotf.«iiiKS Lomarcki, Park. Upper Chalk (? zone of Holaster planus), locality unknown. 
Museum of Practical Geoloity, Xo. 21237. Variety with concave anterior area. Right valve and 
anterior view, x J. 



32(5 



CRl-rrACEOUS J.A.MI'JLLIUKAXCIIIA. 





.-^^r 



Fig. 8G. — Jnoceramus. A variety cnnncctinu^ 1. l,itni<ir<l,i witli [. involutus. Upper Chalk, probably Kent. 
Sedgwick Museiiui Riijlit valve displnt'i'il. Posterior view, x J. 



'7^^- 




FiQ. 87. — .\nteri(ir view of specimen shown in Fig. 86. Natural size. 



lAOCEKA.MlS. 327 

I.Jiifiis-, ]\raiitfll ( Fiu'. 7<)), from tlio Uiipcr (Mialk near Brighton ; in tlie Britisli 
Museiini, No. -"iSJ-S. 

T. I'rouguiarti, Sowerby, 182o (Fig. 70). I;Ocality and hoi'i/on unknown ; in 
tlie British Mnsevnn, Xo. -l-o2(j5. 

The small specimens from the /one of lilii/iiclnnii'llii C'liriri-l near Camljridge, 
figured by Etlieridge as Iiuiccr((iiinH jiroltlein<ificiif<, ari' in the Museum of Practical 
Geology (Xos. 2 1 230-2 1 232). 

Distfihidioii. — /. fjiDiiiin-J.-l ranges from the zone of IllDjiirlniiirlhi Cavieri to the 
zone of ?\[icraf<tpr ciir-mujui iiniu} 

Zone of Tilij/itchonclhi I'm-icri -. St. Catherine's Ilill (Winchester), the Isle of 
Wight, Cuxton, Bnrhani, Dunton Green, the Sussex coast, Dover, Hitchin, Fovil- 
bourn near Cambridge, the Yorkshire coast. 

Zone of 'rprrJii-iifiilimi lufn ; Hooken (South Devon), the Isle of Wight, Cuxton, 
Blue Bell Hill (Bui-hani), Dunton Green, Kenlev, Westerham, Lewes, the Sussex 
coast, Holborough near Rochester, Dover, Guilford Colliery (Coldred near Dover), 
Hitchin, Koyston, the Yorkshire coast. 

Zone of Ifnh(sf('r j}l(nnis .- The South Devon and Dorset coasts, the Isle 
of Wight, Winchester, Ilomington (Salisbury), Cuxton, Borstal, Whyteleaf 
(AV;irlinghain), the Sussex coast, Dover, Newmarket, Swaffham (Norfolk), 
Westacre, Xarborongh, the Yorkshire coast. Chalk Rock of Cuckhamsley. 

Zone of Micraster cor-tcstaiVuiariinn : The South Devon and Dorset coasts, the 
Isle of Wight, Borstal Fort, Borstal Manor pit, Chatham, Lewes, the Sussex coast, 
Dover, Wharram Percy, the Yorkshire coast. 

Zone of Minnisfrr cor-anguinnm : The Dorset coast, the Isle of Wight, Camp 
Hill (Sali-sbury), ^licheldever, Harefield, Southeiam, the Sussex coast, St. 
Margaret's, Thanet, the Yoi-kshire coast. 

Senonian of Ifaldon. 



iNOCERAAirs ixvoi.iTrs, Soiri'rhi/, 1828. 'i'ext-figs. 88 — 94. 

1828. Inoceramus involutus, .7. tJi- C. Soirerhy. Miu. Couch., vol. vi, p. 16i), 

pi. dlxxxiii, figs. 1 — 3. 
1841. — — F. A. lii'iiiii-. ])ie Versteiu. d. uord-deutscli. 

Kreidegeb., p. 61. 
1846. — — A. <rOrhS,jnij. Pal. Franc. Terr. Crct., vol. iii, 

p. 520, pi. ecccxiii, figs. 1 — 3. 
— — Lamakckii, d'Oihitjiiij. Ibid., p. 518, pi. in-cxii. 

1850. — INVOLUTUS, d'Orbigny. Prodr. de Pal., vol. ii, p. 250. 



' Some authors have recorded this species \'vi>nt thezouesof ifdi-fiiiiillfs iesliiiJInartiis, 4^cliiiocamax 
quadfatug and Bilciiniilelln iiiiirruiKilii, but I have not sufficient evidence to confirm these records. 



328 CRETACEOUS LA.MELLIBRANCHIA. 

1850. Inoceramus involutcs, J. de C. Sowerly, in F. Dixon. Geol. Sussex, p. 

355 (p. 386, ed. 2), pi. xxviii, fig. 32. 
1854. — —J. Morris. Cat. Brit. Foss., ed. 2, p. 169. 

1863. — — A. V. Siromhecl: Zeitscbr. d. deutsch. geol. 

G-esellsfli., vol. xv, p. 127. 
1871. — (VoLvicER.^Mfs) INVOLUTUS, F. StoUczkii. Pulwout. ludica, 

Cret. Faumi S. ludia, vol. 
iii, pp. 394, 401. 

1875. — INVOLUTES, C. Df'cocq. Assoc. Franc. Avaiic. Sci. (Lille, 

1874), p. 367. 

1876. — — D. Bra II III!. Zeitselir. f. d. gesanimt. Naturwiss., 

vol. xlvi. p. 379. 

1877. — — C. Svlil'^ter. PAl8eoutoi,'raplii(.-a, vul. xxiv, ].. 27-_'. 

1878. — — C. Barrois. Ann. Soc. gi'ul. du Nord, vol. v, 

p. 475. 
1888. — • (VoLviCEUAMUs) IN'VOLUTUS, Cr. .W/(7/(>/-. Jalu'b. d. k. preus.s. 

geol. Landesanst. fiir 1887, p. 411, 
pi. xvi, figs. 3, 4. 
— — ixvoLUTUs, A. Pemii. Hist. Terr. Craie S.E. du Bassiii 

Auglo-Pai'isien, p. 157. 

1901. — — F. Sliinii. Jalirb. d. k. preuss. geol. Landesanst. 

fiir 1900, vol. xxi, p. 91, pi. ix, fig. 4. 

1902. — — A. Wolleiiianii. Liineburg. Kreide (Abliaudl. d. 

k. prtuss. geol. Landesanst. 
N.F., 37), p. 68, pi. i, fi;,'. 4; 
pi. ii, figs. 7, 8. 
1906. — — G. Smolei'igM. Bull. Intern. Acad. Sci. Cracovie, 

p. 721. 

1909. — — J. Nnwal: Ibid.. \<. 874, pi. xlvi, figs. 4, 5. 

1910. — — J. Bvhin. CVntralbl. fiir Min., etc., p. 741. 

DescrlpHon. — Bliell very iiu'(|uivalvr and wvy iiiequilatei-al. Riglit valve oval 
or semi-oval in outline ; usually slig'litly coiive.x. I)ut .sometimes either more convex 
or nearly fiat, with the uuirginal part in old specimens forming an obtuse angle 
with the earlier part, liength greater than height. Anterior and ventral margins 
rdunded ; posterior margin forming usually an obtuse angle l)ut sometimes nearly 
a right angle with the hinge. Umbo usually incdnspicuons, at or near the 
anterior end of the hinge-line. Hinge-line e(iuals about thrt'c-cpiarters of the 
length of the valve. Postero-dorsal nuirginal part convex near the hinge and 
separated by a sharp furrow from the remaimlei' of the \alve. Ornamentation 
consists of strong, somewhat irregular concentric folds, with an un.symmetrical 
curvature; the folds are sej^arated l)y broad, concave interspaces. In casts of this 
valve, ami sometimes in the shell itself, radial markings ai'e seen in the concave 
interspaces. 

Left valve much lai-ger than the right, inflated, more or less considerably 

\ 



IXUCERAMUS. 



32'.> 




Fig. 88. — Inuccramits involatiis, Sow. Upper Chalk, locality imknciHn. The tyn'. British Museum, Xo. 

43268. Left valve. Natural size. 





Via. H9. — hiortr<imiit iiivolulua. Hkw. The ori^'inal of the .■^poeiiiieil fi.,'Uiivl iu I)i.\on'.s ' Ueol. Sussex." pi. 
.vxviii. fi;;. -.i'. Upper Chalk, Charinj,'. Flint east. British Museuui, Xo. LS.J. Natunil size. 



:3:30 



CRETACEOUS L.UIELLIFiRAXCHIA. 




J 





J^'l 



Fiii. 'M. — Inoccriiiiius involntus.Sow. Upper Chalk, probably Kent. British Museum, No. Li'Jl". Posterior 
view. Uinboiial part of left valve missing. Natural size. 




< r 



f 







\ 




KiG. 91.— Anteririr view of specimen shown in Fig. 90. Natural size. 



IXOCERAMUS. 






spiral ; witli a very lar^'c iiiubo near the anterior end, ciirveil iiiwai-ils ami 
forwards. Surface nearly sinootli, except for the presence of n'rowth-lines. 

Tlie liinge (Fig. 94) curves at either end ; it is thinnest near the umln) and 
becomes thicker towards the posterior end. The ligament-pits are deep, almost 
square, but sometimes oblong, and increase in height from the umbo posteriorly. 



1^. 



% 



/ 



I 




Fio. 92.— Ki^ht viilve and part of left valve of specimen shown in Figs. 90, 91. 

AfUnUies. — I. inrolufns i& the type of the genus or sub-genus Volcicem))nis of 
Stoliczka. In general appearance this differs considerably from other species of 
Inoceramus, so that its separation as a distinct genus or sub-genus seems at first 
sight (juite justifiable ; but the study of a large number of specimens of /. iiiroliitiis 
and I. Lamarcki shows that these two species arc very closely allied, and that the 
former has almost certainly descended from the latter. Such being the case it 
follows that these two species are more nearly related to one another than aiv 



332 



t'KKTACKOU.S J.A.MElJ.IHKAXClllA. 



several species wliicli are jilaecil liy all writers in the genus Iiioceramns. In this 
respect Volriceraman is exactly coniparalile with Jcfinoceramitu (p. 268). 

A fairly complete passage can l)e traceil from T. Lamairli tn [. inruliifi(.<i. In 
some forms of /. Lumarcld the valves l)econie more uiuMjual than usual, the left 




Fill. 9;J. — hioceramns inmhitiis. Sow. Upp:M- Chalk, locality unkuowu. British JIusoum, Xo. L21005. 

Anloiior view of left valve. x J. 

valve being relatively larger and witli less distinct folds, and the right relatively 
less convex and its anterior area slightly concave (Fig. 85). These are connected 
with some varieties of /. iiirohdiis by intermediate foi'ms (Figs. 8(3, 87) in which 
the left valve possesses neai'ly all the characters of /. iiirulntiis l)ut is less curved 
and possesses a concave anterior area, whilst on the right valve the folds are 
almost as ]irominent as in I. iurolutus, but the flattened or concave anterior area 



TNOCERAMTTS. 



333 



and a relatively short hinge are still retained, and the right valve is still convex 
and has a concave anterior area. A variety of /. vivolufiifi links snch intermediate 
forms with typical examples of involidus ; in that variety the right valve is rather 
more convex than in typicnl forms, the left valve is not so distinctly spiral, some 
trace of the anterior flattened or concave area is still retained, and the hinge-line 
is rather shorter relativelv. 




-- «;jv:^pxEmq 




Fig. 91. — /iiorcramus into(«(ns, Sow. Upper figure : Zone of iVic)"as(error-niigHiiir(«i. Gravesond. Sedgwick 
Museum, Cambridge. Kiglit valve witli marginal growth round the hinge, x J. 
Lower figure : Hinge of right valve ; Upper Chalk, Norfolk. Norwich Museum, No. 3355. The anterior 
part of the hinge is partly concealed by the marginal growth of the shell, x |. 

/. nmhnnatns, Meek and Hayden,' fiom Fort Benton, Missouri, is, as stated by 
Meek, very closely allied to, and perhaps identical witii, /. incolidHS. Another 
related form is /. exogyroides. Meek and Hayden.'^ Both are regarded as synonyms 

1 'Invert. Cret. and Tert. Foss. U. Missouri' (1876), ]>. 44, pi. iii, fi<.'. 1 : jjI. iv. tigs. 1, 2. 

2 Ibid., p. 46, pi. V, fig. 3. 

44 



334 CRETACEOUS LAME] .LTRTJANCHIA. 

of I. involutiis by Barrois. /. Koeneni, Miiller,' is probably a variety of 
/. involntus in which the riijht valve is more convex and its umbo more prominent 
than usual. 

The right valve of the specimen figured by d'Orbigny (184G, pi. ccccxii, 
figs. 1, 2) as I. Lamarclci is an example of /. involntus; but the left valve (fig. 3), 
if it belongs to the same individual, is probably incorrectly drawn. 

Remarks. — Examples of this species often reach a large size, and in such cases 
the hinge (Fig. 94) may attain a considerable thickness, but portions of it are 
not often found separately. In old specimens the marginal part of the right 
valve grows obliquely or almost at right angles to the earlier part, and the folds 
become indistinct or disappear altogether; and in the right valve this marginal 
growth sometimes occurs along the hinge, owing no doubt to the increase in size of 
the left valve in which it then fits like an operculum (Fig. 94). The hnigtli varies 
in proportion to the height, so that in some forms the right valve becomes nearly 
circular. 

Tijpes. — The type (Fig. 88) is in the British Museum, No. 432G8 ; its locality is 
unknown. The specimen figured in Dixon's ' Geology of Sussex ' (Fig. 89) is also 
in the British Museum, No. L83 ; it is a flint cast and came from the Upper Chalk 
of Charing. 

Distribution. — /. involntus is found in the zone of Micrastcr cor-testudinarinni 
and the lower part of the zone of M. ror-angninuui, being particularly common at 
the latter horizon." 

Zone of M. cor-testudinarium : Chatham, Dover, and Seaford, Sussex. 

Zone of M. cor-anguinum : Winchester, Quidhampton, Mapledurham, Thanet, 
St. Margaret's, Guilford Colliery (Coldred near Dover), the Sussex coast, Lewes, 
Haling pit (South Croydon), Strood, New Brompton (Chatham), Gravesend, 
Harefield near Rickmansworth, Bury St. Edmunds, Saham Toney, Thetford, 
Brancaster, and other places in Norfolk. Between the zones of M. cor- 
testudinarium and M. cor-anguinum near Beverley, Yorkshire. Senonian of 
Haldon. 

Inoceramus cokdiformis, Sowerby, 1823. Plate LIII, fig. 8. Plate LIV, figs. 2—4. 

1823. Inoceramus cokdiformis, J. d<: C. Sowerby. Miu. Couch., vol. v, p. Gl. 

pi. ccccxl. 
183G. — — A. Goldfu.<'s. Petref. Germ., toI. ii, p. 113, 

pi. ex, fig. 6b (not 6a). 



' Jahrb. d. k. preuss. geol. Landesanst.' fiir 1887 (1888), p. 412, pi. xvii, fig. 1. 
2 This species has been recorded by Griffith and Brydone from the Vintacrinus baud of the 
Marsupites zone of Ropley, Hampshire : and by Barrois fnmi the zone of Actinocamax quadratus of 
Newhaven. 



TN0CERAMU8. 335 

1854. Inoceramus CORDIFORMIS, /. Morris. Cat. Brit. Foss., wl. 2, p. 109. 

1897. — R. Leonhard. PalieontograpluLa, vol. xliv, p. 48. 

1898. Haenleini, G. Midler. Mollusk. Uiitersen. v. Brauuschweig 

u. Ilsede (Abhaudl. d. k. preuss. 
geol. Landesanst., n.f., 25), p. 41, 
pi. V, fifj. 7 ; pi. vi, figs. 1, 2. 
?1911. — coViUiYoiiuis, W. Ro(jala. Bvdl. Iiiternat. Acad. Sci. Ciacovie, 

p. 170, pi. iv, fig. 2. 

Non 1904. — _ 0. Airaghi. Boll. Soc. geol. Italiana, vol. .xxiii, 

p. 189, pi. iv, figs. 6—9. 

Descriptiou. — Shell inflated, eciuivalve, very inequilateral, rouucled. Anterior 
margin more or less nearly straight or undulating, l)ut rounded in large specimens. 
Venti'al and posterior margins more or less sinuous. Anterior part of valves 
more or less flattened and often nearly perpendicular to the plane between the 
valves. Postero-dorsal part of valves much compressed and usually wing-like. 
Hinge equal to more than half the height of the shell. Umbones terminal, large, 
prominent, curved inwards and forwards. A broad, shallow sulcus extends from 
behind the uinl)o to the postero-ventral extremity and separates two broad, 
rounded ridges. A similar sulcus nuiy extend from the front of the uml)o to the 
opposite ventral margin. 

Ornamentation consists of broad, rounded, concentric folds, which bend 
upwards where they cross the two radial sulci. The folds become less distinct 
on the anterior and postero-dorsal parts than on the sides of the shell. Numerous 
close-set growth-lines are present. 

Affinities. — /. Haenleini, Miiller,' from the lower part of the Lower Senonian of 
Brunswick and Ilsede, seems to be hardly distinct from /. cordiformis. The 
smaller English specimens agree very closely with one of the examjiles figured liy 
Midler (pi. v, fig. 7). 

/. cordiformis resembles some of the more convex forms of /. Lumarcki, 
Parkinson, from which it is distinguished by the ecjual size of the valves and the 
presence of radial sulci. The specimen, figured (I'l. LIV, fig. 1), connects this 
species with I. Lamarchi. 

Remarks. — Goldfuss' fig. (ii is a copy of Sowerby's figure ; his fig. (i'( is the 
type of /. .'^a.eniiiriiii, Petrascheck. 

Ti/pe. — In the British Museum, No. 43277, from the Upper Chalk (zone of 
Micraster cor-anguinum) of Gravesend (PI. LIII, fig. 8). 

Distribution. — Zone of Micraster cor-testudinariuni of C.'lanfield (Hampshire), 
and Wharram Percy (Yorkshire). Zone of MicraMer cor-anguinum of Gravesend, 
Micheldever, and Portou. Uintacrinus band of Salisbury. Senonian of Haldon. 

' 'Mollusk. Uutersen. v. Biauuschweig u. Ilsede' (1898), p. 41, pi. v, tig. 7; pi. vi, tig.s. 1, 2. 



336 CRETACEOUS LAMELLIBRANCHIA. 



Inoceeamus costellatus, sp. nov. Plate LIV, figs. 5 — 7. 

1897. Inoceeamus, sp., H. Woods. Quart. Journ. Geol. Soc, vol. liii, p. 381, 

pi. xxvii, figs. 14 — 17. 

Description. — Shell small, vei\y inequilateral, rather hig-lier than long, of 
moderate convexity — the greatest convexity being between the umbones and the 
postero-ventral extremity. Umbones terminal. Hinge equal to about three- 
quarters of the length of the shell, and forming more than a right angle with the 
anterior margin. Anterior margin moderately convex, ventral margin very 
convex, posterior margin slightly convex. 

Right valve with a small, pointed, slightly curved umbo. Posterior and postero- 
dorsal parts of the valve flattened A small, flattened antcro-dorsal area is nearly 
perpendicular to the plane of the valves. 

Left valve more convex than the right ; postero-dorsal part compressed, but 
not forming a definite ear. Umbo narrow, pointed, curved inwards, larger and 
more prominent than tlie umbo of the right valve. Antero-dorsal area larger 
than on the right valve. 

Concentric ribs narrow, sharp, usually widely separated; interspaces broad 
and shallow. The curvature of the ribs is very unsymmctrical ; the ventral part 
is very convex, the posterior part only slightly convex. 

Bemarlis. — This species is fairly common in the Chalk Rock. All the speci- 
mens seen are casts. Some examples, Avhich appear to be a variety of this species, 
have small ribs of uniform size. 

Affinities. — This species appears to be related to some foi-ms of /. Lainarrl-i, 
Parkinson, but the left umbo is narrower, more pointed, and less curved ; the line 
of gTeatest convexity is more oblique to the hinge-line, and the posterior and 
postero-dorsal parts of the valves are more conijiressed.' 

Type. — From the Chalk Rock of Cuckhamsley, in the Sedgwick Museum, 
Cambridge. 

Distribution. — Chalk Rock of Dover, Guilford Colliery (Coldred near Dover), 
the Sussex Coast, south-east of Calstone Willington, Cuckhamsle}', Blount's Farm 
near Marlow, Luton, Wallington near Baldock, ]3arley near Royston, and 
Underwood Hall near Dullingham. Zone of HoJastcr jilnnns of South Devon, the 
Dorset Coast, the Isle of Wight, Lichfield (Hants), Winchester, etc." 

' Corapaiv also /. iinJulaliis, Eogala, • Bull. luteruat. Acad. Sci. Cracovie' (1911), p. 171, pi. iv, 
fig. 7, and /. Frecld, Audert, ' Inooeraineu d. Kreibitz-Zittauer Sand stein geb.' (1911), p. 51, pi. i, 
fig. 8. 

2 Recoi'ded iiy Rowe froui tlic zones of Terebraluliiia lata and Micraster cor-anguinum of Dover. 



IN0(1KRAI\IUS. 



337 



Inoceramus digitatus, Sowerby, 1829. Text-fig. 05. 

1829. Inockramtts digitatus, J. cle C. Sowerbtj. Miu. Conch., vol. vi, p. 215, 

pi. dciv, fig. 2. 
1854. — — /. Mf,rn>'. Cat. Brit. Foss , e.l. 2, p. 169. 

? 1875. — — C. Di'cocq. Assoc. Fran9. Avanc. Sci. (Lille, 

1874), p. 368. 

Remarlis.- — This species attains a large size, but is known only Ijy small 




Fio. 95. — Inoceramus di'jitnlus, Sow. The typt-. Fi-oin tlie Drift (JerivuU from tlie Ciialk). Uritish 

MuseKiii, No. 43273. x J. 



portions of the shell of which the exact horizon cannot be determined. The 
ornamentation consists of broad, rounded, radial folds, which diverge very 
gradually and are separated by broad rounded interspaces. Small concentric 
ribs occur, and at distant intervals, broad, gentle, concentric folds can be traced. 
The form referred to /. (Jiijiiatus by Schli'iter differs from that species in having 



/ 



338 CRETACEOUS LAMHLI/IHKAXCHIA. 

diverging and distinctly curved ribs. 7. di(/itafiis appears to be closelj' allied to 
/. subcardissoide>^-, Sclili'itcr. 

Ti/))f. — From the Drift (derived from the Chalk) ; locality unknown. In the 
British Museum, No. 43,273. 

Distrihdion. — No undoubted specimens obtained directly from the Chalk have 
been seen. 



Inoceramus PiNNiFORMis, WiUetf, 1871. Text-fig. 96. 

1871. Inocekamus pinnifoemis, II. Willett. Cat. Giet. Foss., Brighton Mus., 

p. 40, uo. 342. 

Description. — Shell very large, much higher than long, of moderate convexity, 
Avith a posterior wing-like part. 

Ornamentation consists of broad, strong, widely separated concentric folds 
which have a nearly symmetrical curvature; the ventral slopes of the folds are 
rather steeper than the dorsal ; in the interspaces are small (sometimes indistinct) 
concentric folds, which give a moi'e or less marked tuberculate character to the 
radial ribs. The latter are rounded, rather numerous, sometimes partly or com- 
pletely divided by a median furrow, and are continued on to the dorsal surfaces 
of the strong concentric folds, but are absent or indistinct on the ventral surfaces. 

Bfrnarks. — A portion of a large Inoceramns named 7. pianifurmiti liy Willett 
resembles 7. sulicardissoiiles, Schliiter,^ but differs from that species Ijy tlie more 
numerous radial ribs and the absence of a broad furrow extending from the umbo 
in a postero-ventral direction. 

Ti/pi'. — In the Brighton Museum. 

DistribiUioit. — Upper Chalk (zone of Ai'tiiiocn imrr qHudrnfiis) of i'.rigliton, and 
three miles east of Sled mere, Voi'kshire. 

• ' Palaeoutograiiliica,' vol. x\lv (1877). p. 271, jil. .xx.wii ; Baimi.s. ' Auu. Soc. gvol. Nord.,' 
vol. V (1878), p. 474-; Wollt'inami, ' Luncbnr^r. Kreide' (1902), p. 70; Wegiinr, ' Zeitschr. d. 
deutsuh. Kt'ol. GivscllsL-h.," vol. Ivii (liMl.")). p. 169; I. (t'oxho/c/i', Dccocq, 'Assoc. Franc. Avaiic Sci.,' 
1874 (1876), p. 371. 



TxorKi^AMrs. 



339 



/i 







■ M 



"V 



*<^'i 







i 



'■Ji-' 







I 






i^^m 







/I I 



f 




Fiu. 91). — /iioi-eraniiis pinni/nimis, Willint. I'lipiT Clmlk (zone of Arlinocamaz i/uaJratHs), Brighton. 
Brighton Museum, Xo. :{42. Portion o£ right valve, x J. 



340 



CRETACEOUS LAMELLTBRANCHIA. 



Inoceramus corrugatus, sp. iiov. Text-fig. 07. 

Bemarlc!^. — This species is at present known only by a small portion of one 
valve. It is of the same general type as /. iVKjitatm, Sowerby, I. imviiforinis, 
Willett, and /. xtihrard'n^soldes, Schliiter, Init owing to the presence of broad, 
strong radial folds tlic radial ribs are arranged in groups of four or five. The 




Fin 97._Jnnccra)iiws enrnigatus, sp. nov. Upper Chalk, Wouldham Cement Quarry, Grays. Britisli 
Museuiii, No. Ti22.")28 (discovered and presented )iy Col. C. E. Sliepherd). Natural size. 

concentric folds are strong and have a steep ventral, and a gentle dorsal slope. 
The growth-lines are distinct and regular. /. cornujafn.-; and the other species 
mentioned may be compared with /. lezemiemis, Decocq,' which is of the same 
type as I. Lamarcki but possesses two radial folds due to the presence of a medial 

sulcus. 

Distribution.— JJ^^ev Chalk, Wouldham Cement Company's Quarry, Grays, 

Essex. 

I Barrois, ' Ann. Soc. geol. ilu Nord," vol. vi (1870), p. 465, pi. 5, figs. 1, 2. 



palcxontoovapbical Socict\>, 1012. 



A MONOGRAPH 



CRETACEOUS LAMELLIBRANCHIA 



ENGLAND, 



HENRY AVOODS, M.A. 

UNIVEKSITY LECTURER IN PALa:OZOOLOOT, CAMBRIDGE. 



VOL. TI. PART IX. 

OSTREID^, RADIOLITID.E, ADDITIONS, DISTRI15UTI0N, 
BIliLIOGRAPHY, INDEX. 

Pages 341—473; Plates LV— LXII. 



LONDON: 
PRINTED FOR THE PAL^ONTOGRA PHIC AL SOCIETY. 

1913. 



PRINTED BT ADI.ARD AND SON, LONDON AND DOKKINQ. 



OSTREID^. 341 

i^ami///— OSTREID^, Lamarck. 
[Omitted from Vol. I, p. 223.] 

The great difficulties in the systematic study of the Ostreidaj have been 
felt by nearly all writers,^ and are due mainly to the extraordinary variation 
in. the form of the shell. This variation has been brought about by changes in the 
physical conditions of habitat, and particularly by differences in the character of the 
surface to which the left valve is fixed ; it is found that the mode of growth and 
ultimate shape of the shell are determined mainly by the size, shape, and position 
of the attached surface, so that commonly any one species shows an amazing variety 
of forms which can, however, be linked together by large series of specimens. A 
further difficulty in the systematic study of oysters is due to the fact that the shell 
usually possesses little or no ornamentation. 

Various generic or sub-generic divisions have been proposed for the Ostreidse, 
e. g. Ostrea, Lopha ( = Aledri/onia), Arctostrea, Exogyra, Amphidonta, Grijphxa, 
Pycnodonta, Gryphseostrea ; but it appears to me that the phylogenetic relationship 
of the species of oysters is more complex than is represented by these divisions, 
and that a natural grouping can only be established when more is known of the 
evolution of the species. The forms with radial folds have usually been grouped 
together under the name Alectryonia ; but there can be no doubt that such folds 
have originated independently in more than one line of descent, and their presence 
does not necessarily indicate close relationship. Thus, for example, Ostrea semi- 
2)la7ia, which has been commonly referred to Alectryonia, appears to be more closely 
allied to Ostrea vesicidaris than to any species of Alectryonia. The Cretaceous 
forms which have been referred to Gryphsea clearly owe their grypheate character 
to the small size of the attached surface,* and can be traced into forms having the 
characters of Ostrea. In studying the Upper Cretaceous oysters of Tunis, Peron^ 
has already noticed that some individuals of a species may present the characters 
of Ostrea, whilst others are exogyriform or grypheate. In the Chalk of England 
Ostrea semiplana is usually ostreiform, but occasionally, when the attached surface 
is behind the umbo, the shell is at first exogyriform, but afterwards becomes 
ostreiform. 

1 See, for example, the remarks of Hill and Vaughan, " Lower Cretaceous Gryphaeas of the Texas 
Region" ('Bull. U.S. Geol. Survey,' No. 151, 1898), p. 24; and Perou, " Descript. Brach., etc, 
Terr. Cret. Tunisie " (1890—91), pp. 105—109. 

- See R. T. Jackson, " Phylogeuy of the Pelecypoda. The Aviculidae and their Allies" ('Mem. 
Boston Soc. Nat. Hist.,' vol. iv, 1890), p. 317 i] H. Douvillc, 'Bull. Soc. gt'ol. France,' ser. 4, vol. x 
(1910), pp. 635, 642. 

' Op cit., p. 107. 

45 



342 CRETACEOUS LAMELLIBRANCHIA. 

In this work Exogyra is retained as a genus since the species dealt with seem to 
be genetically related, but it is probable that the exogyriform type has originated 
independently in some earlier deiDOsits. It is even possible that a few species 
referred to Ostrea may have arisen from an exogyriform type by the increase in the 
size of the attached surface, and the gradual loss of the spiral character of the 
umbo. 

In the Ostreidpe, perhaps even more than in the case of hioceramns, the number 
of figures which can be given is altogether insufficient to convey an adequate idea 
of the great variability of the species. It is only by the study of very extensive 
collections of specimens that one can hope to arrive at satisfactory conclusions. 

Genus — Ostkea, Linnseus, 1758. 
(' Sjst. Nat.,' eJ. 10, p. 696.) 

Ostrea diluviana, L. Text-figures 98-138. 

1767. Ostrea diluviana, Linnxtis. Syst. Nat., ed. 12, p. 1148. 

1768. G. W. Knorr and J. E. M. Walch. Eecueil. Mon. Catastr. Petrificat., 

vol. ii, ji. 123, pi. D ii, figs. 5, 6. 
1779. " Getphite," B. Faujas-St.-Fond. Hist. nat. Mont. St. Pierre de Maes- 

tricht, p. 151, pi. xxiv, figs. 1, 2. 
1806. OsTEEA PECTiNATA, Lumarck. Ann. du Museum, vol. viii, j). 165 ; vol. xiv, 

1809, pi. xxiii, f. 1. 

— — CAEINATA, LamarcJc. Ibid., vol. viii, p. 166. 

1811. — FRONs, J. Parkinson. Organic Eemains, vol. iii, p. 217, pi. xv, 

fig. 4. 
1813. OsTEACiTES PLiCATissiMtrs, E. T. V. ScJilotheim. In Leonbard's Taschenb. 

fiir Miu., vol. vii, p. 112. 
1819. Ostrea coltjbrina, Lamarch. Anini. sans Vert., vol. vi, j). 216 {non 

Goldfuss). 

— — CAEINATA, Lamarch. Ibid., p. 216. 

— — DILUVIANA, Lamarck. Ibid., p. 214. 

1821. OsTEAciTES DiLuviANUs, G. WaMenberg. Petrific. Tellur. Suecanse, p. 58. 

1822. OaiiBEA CAEINATA, /. Sowerly. Min. Conch., vol. iv, p. 89, pi. ccclxv. 

— — — G. B. Sotverhij. Genera Eecent and Foss. Shells, No. 

vi, fig. 1. 

— — 8EREATA, G. Ciiviev and A. Brongniart. In Cuvier's Ossemens 

Fobs., vol. ii, pt. 2, pp. 251, 599, pi. iii, fig. 10. 

— — CAEINATA, Cuvier and Brongniart. Ibid., pp. 320, 599, pi. iii, 

fig. 11. 
' 1824. — MACEOPTEEA, J. de C. Sowerly. Miu. Conch., vol. v, p. 105, pi. 

cccclxviii, figs. 2, 3. 



OSTREA. 343 

1827. OsTREA DiLTJviANA, S. Nilssoii. Petrific. Suecana, p. 32, pi. vi, figs. 1, 2. 

— — — O. P. Deshayes. Hist. nat. Vers et MoUusques 

(Encycl. method.), vol. iv, pi. 
clxxxvii, figs. 1, 2 ; pi. clxxxviii, 
figs. 1,2. 

1832. — CAEiNATA, Deshayes. Ibid., vol. ii, p. 301 ; Planches, vol. iv, 

pi. clxxxvii, figs. 3 — 5. 

1833. — — A. Goldftiss. Petref. Germ., vol. ii, p. 9, pi. Ixxiv, 

fig. 6. 

— — PECTiNATA, Goldfuss. Ibid., p. 9, pi. Ixxiv, fig. 7. 

— — PRiONOTA, Goldfuss. Ibid., p. 10, pl. Ixsiv, fig. 8. 

— — SEREATA, Goldfuss. Ibid., p. 10, pl. Ixxiv, fig. 9. 

— — niLUviANA, Goldfuss. Ibid., p. 11, pl. Ixxv, fig. 4. 

1835. Alectryonia Defrancii, G. Fischer de Waldheim. Bull. Soc. Imper. Nat. 

Moscou, vol. viii, p. 113, pl. iii. 
? — — Ferussaci, Fischer de Waldheim. Ibid., p. Ill, pl. iv. 

1836. OsTREA eetusa, /. de C. Soiverhy. Trans. Geol. Soc, ser. 2, vol. iv, pji. 

338, 361, pl. xiv, fig. 4. 

1837. — DiLuviANA, W. Hisinger. Lethaea Suecica, p. 49, pl. xiv, fig. 5. 

— — — F. Dujardin. Mem. Soc. geol. de Prance, vol. ii, 

p. 230. 
? — — GREGARiA, F. C. L. Koch and W. Blinker. Beitr. nord-deutsch. 

Oolithgebild., p. 50, 
pl. vi, fig. 2. 
1839. — RECTANGULARis, F. A. Bonier. Verstein. nord-deutsch. Oolithen- 

geb., Nachtrag, p. 24, pl. xviii, 
fig. 15. 

— — DILUVIANA?, H. B. Geinitz. Char. d. Schicht. u. Petref. des silchs. 

Ereidegeb., pt. 1, p. 19. 
1841. — MACROPTERA, F. A. Bonier. Die Verstein. d. nord-deutsch. 

Kreidegeb., p. 45. 

— — CARiNATA, Bonier. Ibid., p. 45. 

— — SERRATA, Bonier. Ibid., p. 45. 

1845. — CARINATA ET 0. PRIONOTA, E. Forhes. Quart. Journ. Geol. Soc, 

vol. i, p. 250. 
1845-6. — DILUVIANA, H. B. Geinitz. Grundr. d. Verstein., p. 478. 

1846. — CARINATA, A. E. Beuss. Die Verstein. der biihm. Kreideformat., 

pt. 2, p. 38. 

— — DILUVIANA, Beuss. Ibid., p. 38, pl. xxx, figs. 16, 17 ; pl. xli, fig. 1 ; 

pl. xiv, fig. 1. • 

— — CARINATA, A. Leymerie. Statist, geol. min. de I'Aube, Atlas, pl. v. 

fig. 19. 

— — PEs-LEONis, E. Forbes. Trans. Geol. Soc, ser. 2, vol. vii, p. 156, 

pl. xviii, fig. 5. 

1847. — NA.CS.OTTERJL, A. d'Orbigny. Pal. rran9. Terr. Crc't., vol. iii, p. 695, 

pl. cccclxv. 

— — CARINATA, d'Orbigny. Ibid., vol. iii. j>. "14, pl. cccclxxiv, figs. 

1—5. 



344 CRETACEOUS LAMELLIBRANCHIA. 

1847. OsTBEA FEONS, d'Orbiguy. Ibid., vol. iii, p. 733, pi. cccclxxxiii. 

— — MiLLETiANA, d'Orhigmj. Ibid., p. 712, pi. cccclsxii, figs. 5—7. 

— — DiLTJviANA, d'Orhifjny. Ibid., p. 728, pi. cccclxxx. 

184-9. — MACROPTERA, T. Brown. Illustr. Foss. Conch. Gt. Brit, and Ireland, 

p. 146, pi. Ivii), figs. 1, 2. 

— — CAKINATA, Brown. Ibid., p. 146, pi. lix, fig. 6. 

1850. — — A. (TOrhifjny. Prodr. de Pal., vol. ii, p. 170. 

— — FEONS, d'Orhigmj. Ibid., p. 255. 

— — MACEOPTEEA, d'OrUgiiy. Ibid., pp. 84, 120. 

— — EicoRDEANA, d'Orbigrty. Ibid., p. 171. 

— — MiLLETiANA, d'Orhig/iy. Ibid., p. 139. 

— — DiLuviANA, d'Orbigny. Ibid., pp. 171, 198. 

— — FRONS ET CAEiNATA, H. B. Gehiitz. Das Quadersandst. oder 

Kreidegel). in Deutscli- 
land, p. 196. 

— — DiLtrviANA, Geinitz. Ibid., p. 198. 

1852. — CARiNATA, F. Burner. Kreidebild. v. Texas, p. 75, pi. ix, fig. 5. 
1851-2. — — H. G. Bronn. Letliaa Geogn., ed. 3, vol. ii, p. 262, 

pl.xxxii, fig. 2. 

1853. — MiLLETiANA, F. J. Pictet and W. Roux. Moll. Foss. Gres verts 

de Geneve, p. 525, 
pi. xlix, fig. 3. 

1854. — MACROPTERA, /. Mom's. Cat. Brit. Foss., ed. 2, p. 173. 

— — FRONs, Morris. Ibid., ed. 2, p. 173. 

1855. — MACROPTERA, G. Cottcau. Moll. Foss. de I'Yonne, p. 122. 

? 1859. — FRONS, T. Wiltshire. Ked Chalk of England (Geol. Assoc), p. 16, 

pi. ii, fig. 4. 
1863. — DILUVIANA, .4. iTwM^/t. Zeitschr. d. deutsch. geol. Gesellsch., vol. XV, 

p. 724. 

1868. — — E. Eichwald. Lethsea Rossica, vol. ii, p. 365. 

— — FRONS, Eichwald. Ibid., p. 366. 

— — CAEINATA, Eichwald. Ibid., p. 367. 

— — EECTANGULAEis, J'. J". Piciei. Melanges paleont., p. 263, pi. xl, fig. 9. 

1869. — MACEOPTEEA, H. Goquand. Mon. Ostiea, Terr. Crct., p. 164, 

pi. Ixxii, figs. 1 — 4. 

— — EECTANGULARis, Coquand. Ibid., p. 187, pi. Ixxii, figs. 5 — 12. 

— — PECTiNATA, Coquand. Ibid., p. 76, pi. xxix, figs. 1 — 7 (0. colu- 

brina). 

— — SERRATA, Coquand. Ibid., p. 79, pi. xvii, fig. 3 ; pi. xxs, figs. 1 — 5. 

— — CAEINATA, Coquand. Ibid., p. 129, pi. xlix, figs. 3 — 9. 

— — RicoEDEANA, Coquand. Ibid., p. 148, pi. liii, figs. 8 — 12. 

— — MiLLETiANA, Coquaiid. Ibid., p. 155, pi. lix, figs. 11 — 16. 

— — DILUVIANA, Coquand. Ibid., p. 120, pi. xl, figs. 1—4. 

— — RECTAnavLA-Ris, P. de Loriol and V. Gillicron. XJrgon. iuft'r. de 

Landeron, p. 25, 
pi. i, figs. 20 — 
22. 
? 1870. — CAEINATA, F. EiJmer. Geol. v. Oberschlesien, p. 333. 



OSTREA. 345 

1871. OsTEEA [Alectryonia] carinata, F. StoliczJca. Pala;out. ludica, Cret. 

Fauna S. India, vol. iii, 
p. 468, pi. xlviii, fig. 5 ; 
pi. xlix, figs. 1 — 2. 

— — — PECTINATA, Stoliczka. Ibid., p. 4G9, pi. xlviii, 

figs. 1, 2. 

— — — DiLUviANA, Stoliczka. Ibid., p. 466, pi. xlvi, figs. 

1, 2 ; pi. xlvii, figs. 
1,2. 

— — MACROPTERA, F. J. Pidet and G. Campiche. Foss. Terr. Cret. Ste. 

Croix (Mater. Pal. 
Suisse.ser. 6),p. 300, 
pi. clxxxiv, fig. 5. 

— — RECTANGULARis, Pictd and Campiche. Ibid., p. 275, pi. clxxxiv, 

figs. 1 — 4. 

— — MiLLETiANA, Pictet and Campiche. Ibid., p. 309, pi. cxciv, figs. 

7-9. 

— — PECTisxTA., Pictet and Cam2}iche. Ibid., p. 321. 

1872. — CARINATA, H. B. Geinitz. Das Elbtbalgeb. in Sachsen (Paleeonto- 

graphica, vol. xx, pt. 1), p. 174, 
pi. xxxix, figs. 6 — 11. 

— — DILUVIANA, Geinitz. Ibid., pt. I, p. 176, pi. xxxix, figs. 1 — 5. 
? — — FRONs, Geinitz. Ibid., pt. 2, p. 30, pi. viii, fig. 12. 

1875. — DILUVIANA, E. Hcbert and E. Munier-Chahnas. Annal. Sci. geol., 

vol. vi, p. 119. 

— — FBONS, A. J. Jukes-Browne. Quart. Jouvu. Geol. See, vol. xxxi, 

p. 295. 

1876. — (Alectryonia) diluviana, D. Brauns. Zuitsclir. f. d. gesammt. 

Naturwiss., vol. xlvi, 
p. 392. 
1878. Alectryonia Zeilleri, E. Bayle. Explicat. Carte geol. France, vol. iv. 

Atlas, pt. 1, pi. clxvi, figs. 1 — 4. 

— — CARINATA, Bayle. Ibid., pi. cxlvii, figs. 1 — 7. 

1881. OsTREA CARINATA, /. Gosselct. Escjuissc gcol. du Noi'd, iii, pi. xvii, 

fig. 4. 
? 1882. Alectryonia frons, H. Schriider. Zeitsclir. d. deutscb. gei>l. Gesellsch., 

vol. xxxiv, p. 261. 

1883. Ostrea DILUVIANA, A. Fritsch. Stud, im Gebiete dcr bijbm. Kreideformat., 

iii, Iserschicbt., p. 120, fig. 95. 

— — FRONS var. MACROPTERA, W. Keeping. Foss., etc., Neoc. Upware 

and Brickbill, p. 102. 

— — — var. CARINATA, Keeping. Ibid., p. 103. 

1884. — MACROPTERA, 0. Wecrth. Neocomsaudst. im Teutoburg.-Walde 

(Palaeont. Abhaudl., vol. ii), p. 55. 

— — RECTANGULARIS, Weerth. Ibid., p. 54. 

— — CARINATA, C. A. White. Foss. Ostreidae N. America (4th Ann. 

Rep. TJ. S. Geol. Surv.), p. 293, pi. 
sliii, figs. 1 — 4. 



346 CRETACEOUS LAMELLIBRANCHIA. 

1886. Alecteyonia macroptera, H. Trautschold. Neocom. Sably (Nouv. 

Mem. Soc. Imp. Nat. 

Moscou, vol. xv), p. 133. 

1888. OsTREA (Alectryonia) diluviana, G. Miiller. Jabrb. d. k. preuss. geol. 

Landesanst. fiir 1887, 
p. 400. 
? 1889. — FRONS, A. Fritsch. Stud, im Gebiete der buhm. Kreideformat., iv, 

Teplitz. Sebicht., p. 87, fig. 86. 

— — (Alectryonia) frons, 0. Griepenkerl. Senoii. v. Konigslutter 

(Paloeont. Abhandl., 
vol. iv), p. 33. 
? 1890. Allectrtonia cf. carinata, M. Yokoyama. Palseontograpbica, vol. xxxvi, 

p. 198. 

1893. Ostrea frons, S.Meunier. Le Naturaliste, p. 175, fig. 1. 

— — carinata, B. Michael. Zeitscbr. d. deutscb. geol. Gesellscb., vol. 

xlv, p. 238. 

— — sp. cf. DILUVIANA, Michael. Ibid., p. 239. 

1894. — DILUVIANA, B. Lundcjren. Mollusk. i Mamniillahis ocb mucrortata 

zonerna, p. 36. 

1895. — (Alectryonia) carinata, E. Tiessen. Zeitscbr. d. deutscb. geob 

Gesellscb., vol. xlvii, 
p. 462. 

— — — rf. diluviana, Tiessen. Ibid., p. 463. 

— — macroptera, G. Maas. Ibid., vol. xlvii, p. 271. 

— ■ — — A. IVollemann. Ibid., vol. xlviii, p. 834. 

1897. — CARINATA, TJ. Sl'/hle. Geognost. Jabresb. (1896), p. 40. 

— — — B. Leonhard. Palasontograpbica, vol. xliv, p. 27. 

— — diluviana, a. Hennicj. Eevis. Lamellibr. i Nilssons's ' Petrit. 

Suecana,' p. 16, pi. ii, figs. 1, 2, 5. 

— — (Alectryonia) pectinata, F. Ndtling. U. Cret. (MaestricbtiiUi) 

Mari Hills (Palajont. 
Iiidica, ser. xvi, vol. i), 
p. 38, pi. ix, figs. 2, 8. 

— — — FRONS, A. Eiitot. Bull. Soc. Beige Geol. Paleoiit. 

et Hydrol., vol. x, p. 24. 
? — — FRONS, A. Fritsch. Stud, im Gebiete der bobm. Kreideformat., vi, 

Cblomok. Scbicbt., p. 68. 

1898. — pectinata, G. Miiller. Mollusk. Untersen. v. Braunscbweig u. 

Ilscde (Abbandl. d. k. preuss. geol. 

Landesanst., n.f., 25), p. 13, pi. i, fig. 6. 
1900. — macroptera, A. Wollemann. Die Biv. u. Gastrop. d. deutscb. u. 

bolliiud. Neocoms (ibid., n.f., 
pt. 31), p. 16. 

1904. Alectryonia Zeilleri, Jf. Bouvilh'. Mission Sclent. Perse (J. de Morgan), 

vol. iii, pt. vi, Palt'ont., p. 277, 
pi. xxxvi, fig. 16. 

1905. Ostrea diluviana, T. Wegner. Zeitscbr. d. deutscb. geol. Gesellscb., vol. 

Ivii, p. 182. 



OSTREA. 347 

1908. OsTREA (Alectryonia) maceoptera, p. a. Peron. Compte rendu Assoc. 

Franf. Avanc. Sci., 
vol. xxxvi (1907), 
p. 308. 

1910. — — CARINATA, E. Buse. Mon. geol. paleont. Cerro 

de Muleros (Bol. Instit. 
geol. Mexico, No. 25), p. 
104, pi. xvi, figs. 13, 14. 

1911. — (Alectronia) cxRiNATA, a. Fritsch. Stud, im Geldete der bohm. 

Kreideformat., Korycaner 
Schiclit., p. 48, fig. 218. 

— — DiLUViANA, Fritsch. Ibid., p. 48, fig. 216. 

— Alectryonia diluviana, K. Vogel v. Falclcenstein. Zeitsclir. d. deutsch. 

geol. Gesellsch., vol. Ixii, p. 659. 
? — — cfr. FRONS, Vogel v. Falckenstein. Ibid., p. 559. 

Nou 1847. OsTREA CARINATA, J. MHUer. Petref. der Aachen. Kreidef., pt. ], p. 38, 

(=0. Goldfussi, Holzapfel). 

— 1850. — — /. de C. Sowerhi/, in F. Dixon. Geol. Sussex, p. 357 {0. 

frons, p. 386, ed. 2), 
pi. xxvii, fig. 2. 

— 1852. — FROas ? B. Ener. Denksclir. k. Akad. Wissenscli. Wien, Math. -Nat. 

CL, vol. iii, p. 319, pi. xvii, fig. 10. 

— 1883. — — A. Fritsch. Stud, im Gebiete der bohui. Kreideformat., 

iii, Iserschicht., p. 121, fig. 96. 



Description. — Sliell nearly equivalve ; the valves similar except for the attached 
surface of the left valve. The proportion of height to length varies, but usually 
the height is much greater than the length, the difference becoming greater with 
age. Valves usually more or less tapering towards the postero-ventral extremity, 
but occasionally expanding at the end ; slightly, moderately, or considerably 
curved, occasionally forming a nearly complete volution ; sides flattened, so that 
in the elongate forms each valve is roof-like in section. The thickness (or depth) 
of the valves increases with age, and in old individuals the shell becomes very 
thick and possesses a vesicular structure. Umbones siniill, with a slight or 
moderate posterior curvature. A posterior wing or ear is usually present, and is 
of small or moderate size when the attached surface is small, but of large size 
when the attached surface is large and mainly posterior to the umbo. A small 
anterior wing is often present, and is best developed in specimens which have a 
small attached surface. When the attached surface is small or narrow the shell 
becomes elongate, but when the attached surface is large and broad the shell 
becomes rounded or oval instead of elongate, and then the posterior ear is usually 
not distinctly defined. 



348 



CRETACEOUS LAIVIETJJBRANCHIA. 




109 



n.fo'- ",?.«''','"? r""' •^'■''^- '^''- ^'''^''y I'-o^'ton^-. Goulsby. Bristol Museum. Left valve and 
anterior view 100-102. Lower Greensand, Atherfiekl. Museum of Practical Geology, Nos. 25802 357«) 
valve' lof O^- 7' ^"'l i!"''^'-''"- V-"- lO:!, Cmckers, Atherfield. Sa.ne museum, Xo. 25793. ' tl^^i 
vave" °^' "l^' J'""'^'- «'-«^<^°«'i";l. Upware. Sedgvvick Museum. Interior and exterior of a feft 
TrearhP,', rT' }^'"'-<'\^^^'-ff'^^^<i> Far.ngdon. 106, 107, Bristol Museum. Left valve. 108. Mr. 
va've kll X ° '' "• ^"■^' ^«"-"^"'0"^ S^"d^' ShankUn. Sedgwick Museum. Kight 



OSTREA. 349 

Valves with strong, usually angular folds which, in the elongate forms, extend 
from the median line to the margin ; the folds are usually somewhat curved, but 
may be almost straight; the amount of their curvature decreases in passing from 
the earlier to the later part of the shell. The margins of the two valves interlock 
by means of sharply pointed tooth-like projections formed by the interspaces 
between the folds. On the median ridge of the valves the folds are usually 
irregular, and may bear on each side of the ridge short spines ; near the margins 
of the valves long tubular outgrowths occur in some specimens. The number and 
size of the folds vary considerably in different individuals ; often the later folds 
are stronger than the earlier ones, and those on the convex side stronger than 
those on the concave side. The part of the right valve near the umbo is smooth 
and without folds so long as the corresponding part of the left valve is attached ; 
this portion is commonly small, but becomes extensive when the attached surface 
of the left valve is large, and then the folds are limited to the relatively small 
marginal part of the valves. The triangular ligament-pit may be slightly or con- 
siderably curved. The adductor impression is oval, and usually not far from the 
hinge-line. 

Affinities. — The examples of this species found in the Lower Cretaceous have 
been named 0. rectanr/ularis, Romer, and 0. macroptera, Romer. Pictet and 
Campiche, de Loriol, and Weerth regard 0. macroptera as distinct from 0. rect- 
angularis, and state that the former differs from the latter principally in the 
relatiA'^ely smaller height of the shell, the larger posterior wing, and the larger 
ribs. D'Orbigny, Maas and WoUemann, on the other hand, consider that the two 
forms cannot be separated. The last author, after studying a large collection of 
specimens, states that the height of the shell depends mainly on the age of the 
individual ; that the size of the posterior wing varies greatly, being in some cases 
quite small, in others very large, and between the two extremes every gradation 
may be found. The size of the ribs likewise varies. The study of numerous 
English specimens leads me to endorse AVollemann's view. Pictet and Campiche 
figured as 0. macroptera a small example from the Lower Greensand of Atherfield, 
but larger specimens from the same horizon possess a higher shell like 0. rcrt- 
anrjuJarls, and cannot be separated from 0. macroptera. 

The examples found in the Lower Cretaceous deposits have been generally 
regarded as distinct from those in the Upper Cretaceous, which in this country 
have been usually named O.frons or 0. carinata. The principal distinction is said 
to be the larger posterior wing in the Lower Cretaceous form. But the study of 
a large series of specimens shows that in both the Upper and the Lower Cretaceous 
the size of the wing varies greatly, as well as the height and curvature of the 
shell, and the number and coarseness of the ribs. As a rule, however, the posterior 
wing is better developed in the Lower than in the L^pper Cretaceous examples, 

46 



350 



CRETACEOUS LA^IELLIBRANCHIA. 




Figs 110-122.— Osf,-ca dihn-iana, L. Sedgwick Museum, except 120, 121. 110, 111, Lower Greensand, 
Upware Left and right valves. 112-119, Lower Groensaud, Faringdon. Lett valves. H-J-JJ*. 
anterior, interior and e.tterior of a left valve. 116, 117, interior and exterior of a left valve, lis, 
119, interior and exterior of a left valve. 120, 121, zone of Peden asper, Devizes. Museum of Practical 
Geology, Nos. 25814, 2oS12. 120, right valve. 121, left valve. 122, Chalk Marl, Folkestone. Loft 
valve. All x J. 



OSTREA. 351 

but in some of the formei' it is small/ while in some of the latter it attains a large 
size (fig. 123), and such specimens are indistinguishable from 0. mncroptera. It 
seems, therefore, that no line can be drawn between 0. macro2)ter(t and the Upper 
Cretaceous forms, especially since it is found that the size of the wing is directly 
related to that of the attached surface of the left valve which was almost certainly 
determined by external conditions. When the attached surface is large and 
mainly posterior to the umbo, then the macropfera type with a large wing arises. 

The examples of this species (here known as 0. diluviana, L.), found in the 
Upper Cretaceous deposits, have received numerous names, of which the principal 
are 0. pcctlnata, Lamarck, 0. carinata, Lamarck, 0. coluhrina, Lamarck, 0. froiis, 
Parkinson, 0. t^errafa, Brongniart, 0. pn'onota, Goldfuss, 0. Millrtidvu, d'Orbigny, 
0. BlrorJcana, d'Orbigny, 0. Zeilleri (Bayle). In the LTpper Cretaceous of England 
this species is not known to occur above the zone of Holaster suhjlohnsus and has 
been usually named O.frons or 0. mrlnnta, but on the continent of Europe and in 
other parts of the world it is represented in the higher parts of the Chalk. 
D'Orbigny and Coquand, believing in the principle that specimens found at different 
horizons belong to different species, have regarded as distinct forms the following 
amongst others : 0. Milletiana from the Gault, 0. carinata from the Cenomanian, 0. 
pedviafa (O.fronx) from the Lower Senonian, 0. scrrata from the Upper Senonian. 
But later authors have found the o'reatest difficult v in distiuQ-uishino- these 
" species." An examination of a large number of specimens, even when collected 
from one locality and one horizon only, shows that the shell is -extraordinarily 
variable, and that every gradation is found between the different types ; apart from 
variation in the number and size of the ribs, the curvature of the shell, etc., there 
are differences which are obviousl}^ duo to the size, shape and position of the 
attached surface. Similar modifications occur at all horizons, and it seems 
impossible to separate as distinct species the forms found at different levels. 
Sometimes at one locality or in one kind of deposit a particular form of the shell 
may be more common than others, and may, if only a small number of specimens 
are available, give the impression of l)eing a distinct species, but whenever a large 
collection is made other varieties are found which make it impossible to regard as 
a species the form which at first sight appeared to be distinct. The difficulty of 
separating these supposed species is shown by the fact that although d'Orljigny 
states that 0. froiis is characteristic of the Senonian, yet he includes in his synonymy 
the specimens figured by Sowerby from the Upper Greensand and Chalk Marl. 
Similarly, in quoting foreign examples of a " species," authors have sometimes 
unconsciously cited them from horizons in which they believed the species did 
not occur. 

' See, for example, a specimen from the Lower Greeusaud of Faringdon (figs. 106, 107), in 
whieh the left valve was attached to a long narrow object, and tlie posterior wing is not developed. 



352 CRETACEOUS LAMELLIBRANCHIA. 

Peron (1908) has already recognised that these "species " cannot be accepted. 
He states that the detailed analysis of the characters attributed to each of the 
species and the study of their synonymy shows that the enchainemeut of these 
diverse forms is complete, and that usually the difference of names corresponds 
only to difference of stratigraphical horizon. 

The form found in the Gault, which was named 0. Milletiaim by d'Orbigny, is 
considered by Pictet and Campiche to be identical with 0. carinata of Sowerby 
from the Upper Greensand and Chalk Marl, which, as already mentioned, is 
included by d'Orbigny in 0. frons of the Senonian. Pictet and Campiche quote 
0. Milletiana from the Cambridge Greensand, but this is included by Jukes- 
Browne in 0. frons. 

0. diliiviaua, Linngeus, from the Upper Chalk of Sweden, was figured first by 
Nilsson, and more recently other figures of Swedish specimens have been given by 
Hennig (1897). D'Orbigny and Coquand recognised that the specimens figured 
by Nilsson as 0. dilnviana could not be separated from 0. frons, and the same 
view is held by Brauns, Lundgren, and Hennig. The two last-named authors 
state that Nilsson's figures certainly represent Linnaeus' species, and Brauns also 
takes them as types of 0. diluviana, but excludes the figures given by d'Orbigny^ 
Coquand, Goldfuss and Geinitz. D'Orbigny, on the other hand, takes Hisinger's 
figure of a specimen from the Upper Chalk of Sweden as the type of Linnaeus' 
O. diluvinna, and excludes from that species the forms figured by Nilsson, which 
he regards as belonging to 0. frons. The examples of 0. diluviana figured by 
d'Orbigny, Coquand and Geinitz come from the Cenomanian. In 0. diluviana, as 
understood by those authors, the shell is oval or rounded in form instead of being 
elongate as in the common forms of 0. frons ; at first sight it appears to be quite 
distinct, and being easily recognisable it has been commonly regarded as a separate 
species,' but Lundgren and Hennig have found in the Swedish Chalk a large 
number of intermediate forms which link together 0. diluviana as interpreted by 
d'Orbigny and 0. diluviana as figured by Nilsson and Hennig, consequently these 
two types cannot be any longer regarded as distinct species. Geinitz, although 
keeping the foi*ms distinct, nevertheless recognises in the Cenomanian of Saxony 
the existence of intermediate forms, and the same fact is shown by Goldfuss' 
figures. An oval or rounded form, closely resembling 0. diluviana as understood 
by d'Orbigny, is found in the Lower Greensand of Faringdon (figs. 115, 118, 
119), and is certainly inseparable from the common elongate form which has 
been usually named 0. macroptera ; similar remarks apply to a rounded form found 
occasionally in the Upper Greensand and Chalk Marl of England (figs. 124, 125). 

^ H. Douville places this iu the "genus" Loplia {— Aledryonia), aud refers the elongate forms 
{frons, carinata, etc.) to the " genus " ^rc^osirea. See 'Bull. Soc. gcol.de France,' ser. 4, vol. x 
(1910), pp. 63G, 637. 



OSTREA. 



353 




Fios. 123-134. — Osliea diliiviana, L123, zone of Sehloenbachia roslrala, Devizes. Musouiii of Practical 
Geology, No. 25820. Riffht valve. 124, 12."), Upper Greensaiul, Sidinoutli. Briti.sli Museum, L3326. 
Left valve. 12(i 130, Clialk Marl, Folkestone. Se(l<;wick Museum. 12G, anterior view. 12S-130, 
right valves. 127, anterior view of 128. 131-133, Base of Chalk Marl, HaslingfieU. Sedgwick 
Museum. Right valves. 13t, Cenomanian Sandstone, Wilmington. Sedgwick Museum. Vertical 
section of left valve. All x J-. 



354 



CRETACEOUS LAMELLIBRANCHIA. 



So that this type occurs at three horizons : Aptian, Cenomariian, and Senonian, 
and its features are obviously due to the harge size and rounded form of the 
attached surface; the shell was attached for such a long period that when it 
eventually grew free it was unable to develop its usual elongate form, and its 
ultimate outline was only a little different from that of its attached surface. 
The coarseness of the ribs varies in the same way as in the elongate forms. In 
some places, as, for instance, in the Cenomanian of Gamighiigel in Saxony, the 
shell attains a great thickness, but the elongate forms likewise sometimes become 
very thick. 




Figs. 135-138. — Ostrea dihti-iana, L135, zone of Molasier sulgloboswt, Cherry Hintou. Kijjht valve. 13G-13S, 
Base of Chalk Marl, Haslingfield, Cambs. 136, 137, Right valves. 138, anterior view of 137. 
Sedgwick Museum. All x ^. 

0. santonensis, d'Orbigny, and 0. carantonensix, d'Orbigny, are similar to 
d'Orbigny's 0. diluviana, and are included by Geinitz in that species. 

Bemarls. — The shell varies greatly in its curvature, some examples being only 
slightly bent, while others form almost a complete volution (fig. 123), and between 
these extremes every gradation is found. The variation in the coarseness of the ribs 
seems, in some cases at any rate, to be connected with the nature and depth of 
the sea-floor on which the individuals lived ; for example, most of the specimens 
found in the Chalk Marl have coarse ribs, but those found in the Cenomanian 
sandstone of "Wilmino-ton in Devon have smaller and more numerous ribs. Occa- 
sionally folds or ribs are developed on the posterior ear (fig. 135). The long 
regular outgrowths from the margin of the valves (fiig. 122) occur in specimens 



OSTREA. 355 

from the Chalk Marl, and were no doul)t developed for the purpose of fixation in 
the soft sediment of the sea floor. 

In all cases the right valve starts with a smooth stage, and folds are developed 
later. The smooth stage corresponds with the attached surface of the left valve, 
since folding does not begin until the margin of that valve groAvs free from the 
rock or body to which the shell is fixed. Occasionally, after folding has gone on 
for some time, a second smooth stage appears on the right valve ; this is due to 
the left valve becoming again attached to a foreign body (fig. 137). 

Types. — 0. dilaviana, L., from the Senonian of Sweden. 0. j'i'ctiiiatu, Lamarck, 
is said to have come from near Dreux (Eure-et-Loire). 0. carinata, Lamarck, 
from Carry (Seine-Inferieure). 0. frons, Parkinson, from France; the locality 
and horizon are unknown, and the specimen cannot now be found. 0. carinata, 
Sowerby, from the Upper Greensand of Chute Farm, near Longleat Park, and from 
the Chalk Marl of Folkestone, are in the British Museum. 0. scrrata, Cuvier and 
Brongniart, came from Dreux. 0. viacrojitera, Sowerby, from the Lower Greensand 
of Folkestone, is in the British Museum. 0. retusa, Sowerby, from the Lower 
Oreensand of Atherfield, cannot be traced. 

Distribution. — Claxby Ironstone (zone of Belemnites lateralis) of South Willing- 
ham. Tealby Limestone (zone of Belemnites hrunsvicensis) of North AYillingham, 
Lincolnshire. Ferna-hed of Atherfield. Ferruginous Sands of Atherfield and 
Shanklin. Recorded by Topley from the Sandgate Beds and Folkestone Beds of 
Folkestone. LoAver Greensand of Faringdon, Brickhill, Potton and Upware. 

Upper Gault of Folkestone. Cambridge Greensand. Upper Greensand (zone 
of Schlcenhachia rostrata) of Blackdown, Devizes, "Warminster and Ventnor. 
L'pper Greensand (zone of Fecten asper) of Devizes. Chalk Marl (zone of Schloni- 
hachia varians) of Ventnor, Folkestone, Haslingfield, Burwell, etc. Cenomanian 
Sandstone of Wilmington. Cenomanian (Meyer's Bed 12) of Dunscombe. Zone 
of Holaster snbglohosus of Cherry Hinton and Burwell. 



OsTKKA LKYirEKir, Lmjmerie [ex Deshayes], 1842. Text-figs. 139, 140. 

1842. OsTREA Leymbeii, [Desbaves, MS.], A. Leijmerie. ili'm. Soc. geol. de 

Fiance, vol. v, pp. 11, 28, pi. xiii, 
fig. 4. 
1845. — — E. Forbes. Quart. Joiu-n. Geol. Soc, vol. i, p. 250. 

1843. — — A. Leymerie. Statist, gi'ol. inin. de I'Aube, Atlas, pi. vii, 

fig. 2. 
1847. — —A. d'Orbigni/. Pal. Frau?. Terr. Cret., vol. iii, p. 704, 

pi. cccclxix, tigs. 1 — 3. 
1850. — — iVOrhignij. Prodr. de Pal., vol. ii, p. 108. 

1854. — Leymeeiei, J. Morris. Cat. Brit. Foss., ed. 2, p. 173. 



356 



CRETACEOUS LAMELLIBRAXCHIA. 



1855. OsTREA. Leymerii, G. Cutleau. Moll. Foss. de I'Youne, p. Hi. 
I860. — — A. Gaudrij. Bull. Soc. gcol. de Prance, ser. 2, vol. xvii, 

J,. 30. 
?1861. — — P.deLnriol. Auiui. luveit. Foss. ilt. Saltve, p. 112. 














\ 




Fig. 139. — Osdva Leymerii, Lcym. MammiUatiis-hcd, Okefoi'd Fitzpaine. British Museum, No. L11597. 

Eight valve, x J. 

1869. — — H. Coquand. Men. Ostrea. Terr. Crct., p. 179, pi. Ixx, 

figs. 14 — 17 ; pi. Ixxi, figs. 6, 7. 
— Leymeriei, p. de Loriol and V. GUlieron. Urgon. lufc'r. du Lau- 

deron, p. 27. 
1871. — ljV.YiiY.iiu, F. J. Pidd and G.Campiche. Terr. Crt't.Ste. Croix (Mater. 

Pal. Suisse, ser. 5), p. 296, pl. cc, figs. 1, 2. 



OSTREA. 357 

1878. OsTEEUM Leymeriei, E. Baijle. £xplica(. Carle gt'ol. Je France, vol. iv, 

Atlas, pt. 1. i<]. cxxx, figs. 1, 2. 
1897. O.STREA Leymeriei, R. B. Nenion. Proc. Dorset Nat. Hist, aiid Antiq. 

Field Club, vol. xviii, p. 73, pi. i, 

fig. 3. 

Description. — Shell large, very thick in old specimens, higher than long; 
nsnally slightly or only moderately inequilateral ; outline ovate, oval, subtrigonal 
or subquadrate. Left valve slightly or moderately convex ; right valve often 
flattened. Umbonal part sometimes nan-ow, sometimes broad. Umbo straight or 




•^•r/ 



Fig. 1-10. — Ostrea Leijmcrii, Leym. Mammillat iis-heA, Okofoitl Kitzpaine. Briti.sb Museuiu, No. L. 11591. 

Interior of part of right valve, x ^. 

slightly curved ; area large, high. Surface of valve.s sometimes smooth, except 
for growth-lamellge, sometimes with radial folds. Attached surface of vari- 
able size. 

Affinities. — This species seems to be related to 0. Germaini, Coquand. It also, 
as de Loriol pointed out, shows some resemblance to some forms of E.eogijra 
sinuata in which the umbo is only slightly curved; but whether it has any -real 
relationship to that species cannot at present be determined. See also 0. cuna- 
hiiht (below). 

Ti/jje. — From the Barremian of Aube. 

47 



358 



CRETACEOUS LAMELLIBRANCHIA. 



Distribution. — Hythe Beds of Aylesford, Kent. ManiiitiUdtun-heiX of Okeford 
Fitzpaine, Dorset. Recorded by Fitton from the Perna-heA and Ferruginous 
Sands of Atlier field. Recorded I)}' Topley from the Atlierfield Beds of Peasmarsh 
and Sevenoaks. 



OsTREA cuxAiJL-i.A, ,SVv'%, 18G1. Text-figs. 141, 1-12. 

1861. OsTREA C0NABULA, H. G. Seeleij. Ann, Mag. Nat. Hist., ser. 3, vol. vii, p. 

117, pi. V, fig. 1. 
— — LAGENA, Seeleij. Ibid., p. 117, pi. v, fig. 2. 

Beacripfidii. — Shell higher than long, either nearly equilateral or slightly or 




Fig. 141. — Ostrea cunabiila. Seel. Cambridge Greensand (base of Chalk Marl). Sedgwick Museum. 
Cambridge. The type of 0. lagena. Seel. Interior and exterior of left valve, x =. 

moderately inequilateral ; when nearly equilateral the outline is often ovate 
or oval. 

Left valve ■with the attached surface either small and near the umbo only, or 
large — sometimes extending to the greater part of the valve ; in the former case 
the valve is very convex, in the latter slightly convex or flattened. Umbonal jjart 
usually narrow and pointed. Area large, usually higher than long ; sometimes in 
the plane of the valves and nearly symmetrical ; in other cases curving inwards, 
outwards or backwards. Surface usually with numerous, rounded, radiating ribs 
crossed by growth-ridges. Adductor impression deep, near the posterior margin, 
oval or more or less quadrate. Right valve nearly flat, with growth-lines only. 

Affinities. — 0. cnnahxda is closely allied to and may be only a variety of 



OSTREA. 



359 




Fio. 142. — Ostrea ninahuJa, Seel. Cambridge Greensand (base of Chalk Marl). A, b, British Museum, 
Xo. ()77K1. c-i. Sed|j:wick Museum. A, B, left valve, c, left ; d. right valve ; B, antt^rior view of c, D. 
F. rii;ht valve with other oysters on the surface, a, left valve. H, i, exterior and interior of a left valve. 
All x §. 



360 CRETACEOUS LAMELLIBRANCHIA. 

0. Lpijmen!, from which it appears to differ in its somewhat smaller ril)s. The 
forms with a small surface of attachment resemble O.bdis.^unensis, Bohm/ but have 
coarser and less regular ribs. 0. lagena, Seeley (fig. 141), is a form of 0. cuwilmhi 
with a very large attached surface, and consequenth- a less convex left Aalve. 

Tiipes. — From the Cambridge Greensand (indigenous). The type of 0. hiijriiii 
is in the Sedgwick Museum, Cambridge ; the type of 0. cinialiula cannot be found, 
but other specimens named by Seeley are in the Sedgwick IMuseum. 

Dititrihiition. — Cambridge Greensand (base of Chalk ]\Iarl), Camljridge. Chalk 
Marl of Burwell. 



OsTREA W.\i.Ki:i;i, Krrpiinj, 1883. Plate LY, figs. 1—3. 

1883. OsTREA Walkeki, W. Keepiiaj. Foss., etc., Neoc. Upware aud Bric-khill, 

p. 103, pi. iv, fig. 4. 

Reiiuirlcs. — This fonn is similar to 0. Germaini and 0. Li'i/iiicrii; the chief 
difference mentioned by Keeping — the inequality of the valves — is not constant, 
and is determined b}' the size of the attached surface. Harbort regards 0. ]\'(illien 
as a synonym of 0. Germaini, Coquand,- but the material available is hai-dly 
sufficient for definite determination. Some of the specimens with a large attached 
surface resemble 0. Oxmana, AVoliemann.'' 

TijiH\ — In the Sedgwick Museum, Cambridge, 

Distribiilion. — Lower Greensand of Upware. 



OsTiiEA VKsirri,Ai(is, Lauunrh, 180(1. Plate LV, figs. 4—0. Text-figures. 14:5—182. 

1779. — B. Faujas-St.-Foitd. Hist. imt. Mto. St. Pierre de Maestricht, 

jil. xxii, fig. 4; jil. XXV, figs. 2, 5. 
18Ut). OsTREA VESicuLARis, Lamars}:. Ann. Mus. Hist, uat., vol. viii, p. IGO, aud 

vol. xiv (1809), p. 375, pi. xxii, fig. 3. 
— — DELTOlDEA, Laiiiarch. Ibid., p. 160; vol. xiv (1809), p. 374, pi. 

xxi, fig. 3 (uou deJtoidea, Sowerbv). 
1816. — ■ , ir. SinitJi. Strata ideiitif. Organised Fossils, p. 7, pi. iii, figs. 5 — 7. 

1819. — VESICULARIS, Lamarck. Aiiimaux sans Vert., vol. vi, p. 2Ut. 

1820. — CONVEXA, T. Say. Amer. Journ. Sci., vol. ii, p. 42. 

1 ' Zeitschr. d. deutsch. geol. Gesellsch.,' vol. li (1899), p. 46(5, pi. xxix, figs. 1—3. 

- Coquand, ' Mon. Ostrea, Terr. Cn't.' (1869), p. 191, pi. Ixvi, figs. 14—16. Pictet and Canipiclie, 
'Terr. Crct. Ste. Croix' ('Mater. Pal. Suisse,' ser. 5, 1871), p. '295, pi. clxxxix, figs. 1—6. Wolle- 
mauu, ' Bivalv ii. Gastrop. deutsoli. u. hoUiindisch. Neocoms ' (1900), ji. 18, pi. i, fig. 4. Harbort, 
'Fauna Sehaumburg-Lippe'scheu Kreidemulde ' (1905), p. 28. 

3 Op. cit. (1900), p. 19, pi. i, fig. 5, pi. ii, fig. 1. 



OSTREA. 3G1 

1822. OsTEEA vEsicuLAEis, A. Bvoiiijniart . In Cuvier, Osseiueus Foss., vol. ii, 

p. 598, pi. iii, fig. 5. 

1823. GRTPHiEA OLOBOSA, /. de C. Sowerhij. Min. Conch., vol iv, [i. 127, 

pi. cecxeii. 

1827. OsTREA VESICULAEIS, 6'. Nilssoii. Petrific. Suecana, p. 29, pi. vii, figs. 8 — 5; 

pi. viii, figs. 5, 6. 

— — HippopoDiuM, Nilss'ni. Ibid., p. 'SO, pi. vii, fig. 1. 

— — CLAVATA, Nilssun. Ibid., p. 30, pi. vii, fig. 2. 

1828. Gryphjea convexa, S. G. Morton. Journ. Acad. Nat. Sci. Philad., vol. vi, 

p. 79, pi. iv, figs. 1, 2. 

— — MUTABiLis, Morton. Ibid., \). 81, pi. iv, tig. 3. 

1832. — EXPANSA, J. de C. Soicerby. lu Sedgwick and Murcliison, Trans. 

Geol. See, ser. 2, vol. iii, pp. 349, 
418, pi. xxxviii, fig. 5. 

— OsTREA vEsicuLARis, 6r. P. Deskaijes. Hist. uat. Vers et Mollusques 

(Encycl. method.), vol. ii, p. 291. 

1833. — — A. Gohlfiis.'i. Petref. Gei-m., vol. ii, p. 23, pi. Ixxxi, 

fig. 2. 

— — HIPPOPODIUM, Goldfuss. Ibid., p. 23, pi. Ixxxi, fig. 1. 

1834. GBYPH.a:A convexa, S. G. Morton. Synopsis Org. Remains Cret. U. States, 

p. 53, pi. iv, figs. 1, 2. 

— — MUTABILIS, Morton. Ibid., p. 53, pi. iv, fig. 3. 

? 1835. Ptcnodonte eadiata, G. Fischer de Wuldheim. Bull. Soe. Imp. Nat. 

Moscou, vol. viii, p. 119, pi. i. 

1837. OsTREA VESICULAEIS, W. Hisitiger. LethEea Suecica, p. 46, pi. sii, fig. 2. 

— — HIPPOPODIUM, Eisinger. Ibid., p. 47, pi. xiii, fig. 4. 

— — CLAVATA, Hisinijer. Ibid., j). 47, pi. xiii, fig. 3. 

— GRYPHiEA siMiLis, G. G. Pusch. Poleus Paliiont., p. 34, pi. iv, fig. 12. 

— Osteea VESICULAEIS, A. d'ArcMac. Mem.Soc. gt'ol.de France, vol. ii,p. 183. 
? — — PROBOSCIDEA, d'Archiac. Ibid., p. 184, pi. xi, fig. 9. 

? — — VESICULARIS, F. Dnjarditi. Ibid., vol. ii, p. 229. 

1838. GBYPHiEA VESICULARIS, H. G. Bronn. Letbsea Geogn., vol. ii, p. 204, pi. 

xxxii, fig. 1. 
1842. — (Ostrea) yEsicvi.AB.is, F. v. Hagenoic. Neues Jabrb. fiir Min., 

etc., p. 548. 
1845. Gryph^ea VESICULARIS, H. B. Geinitz. Gnmdr. d. Verstein., p. 483, 

pi. XX, figs. 17, 18. 
1845. Ostrea vesicularis, A. d'Orhigny. In Murchison, de Verneuil and de 

Keyserliug, Gi'ol. Russie de 
I'Enrope, vol. ii, p. 491. 
184ti. — — A. Leymerie. Statist, gt'ol. min. de I'Aube, Atlas, 

pi. iv, fig. 1. 

— — — A. E. Reuse. Die Verstein. der biihm. Kreideforuiat., 

pt. 2, p. 37, pl. xxix, figs. 21. 22; pl. 
XXX, figs. 1 — 8. 

— HIPPOPODIUM, Betiss. Ibid., p. 39, pl. xxviii,figs. 10 — l.j. 17, 18 

pi. xxix, figs. 1 — 18; j)l. XXX, figs. 
13, 14 (r 2>c>'ti»t)- 



302 CRETACEOUS LAMELLIBRAXCHIA. 

1847. OsTREA HippopODiuM, A. iVOrbiijiiy. Pal. Frau9. Terr. Crct., vol. iii, p. 

731, pi. cccdxxxi, figs. 4 — 6 ; pi. 
cccclxxxii. 

— — VESicuLARis, d'OrhiijHij. Ibid., p. 742, pi. cccclxxxvii. 

— — — /. Mailer. Petref. der Aachen. Kreidef., pt. 1, p. 37. 

— — HIPPOPODIUM, Midler. Ibid., p. 39. 

1849. Grtph.ea globosa, J. Broirn. Illustr. Foss. Conch. Great Britain and 

Ireland, p. 148, pi. Ixi, fig. 2. 

1850. — — var. DEPREssA, J. de C. Sotverbij, in F. Dixon. Geol. 

Sussex, p. 357, pi. xxvii, fig. 3. 

— OsTEEA SP., Sowerby. Ibid., p. 357, pi. xxviii, figs. 22, 23. 

— Gryph^a VESICULARIS, E. Kiier. Kreidemerg. v. Lemberg (Haidiuger's 

NatuiTviss. Abhaudl., vol. iii, pt. 2), 
p. 30. 

— OsTREA VESICULARIS, A. Altli. Geogn.-palsBont. Beschreib. v. Lembei'g 

(ibid., vol. iii, pt. 2), p. 252. 
? — — HIPPOPODIUM, Alth. Ibid., p. 253, pi. xiii, fig. 3. 

— — VESICULARIS, A. d'Orbigny. Prodr. de Pal., vol. ii, p. 256. 

— — Lesueuri, d'Orbigny. Ibid., p. 171. 

? 1851. — NiLSSONi, /. Midler. Petrefact. Aachen. Kreidef omiat., pt. 2, 

p. 70. 

— VESICULARIS, A. Leymerie. Mem. Soc. gcol. de France, ser. 2, vol. iv, 

p. 202, pi. X, figs. 2, 3. 
1851-2. GRYPH.t;A VESICULARIS, H. G. Bronn and F. Riimer. Lethsea Geogn., 

ed. 3, vol. ii, pt. 5, p. 264, pi. xxxii, fig. 1. 
1852. — — B. Kiter. Denkschr. Akad. Wisseusch. Wien, 

Math.-uat. CI., vol. iii, p. 319. 
? — OsTJiEA VESICULARIS var. AUCELLA, F. Biimer. Kreidebild. v. Texas, p. 74, 

pi. ix, fig. 4. 
1854. — HIPPOPODIUM, J. Morris. Cat. Brit. Foss., ed. 2, p. 173. 

— — VESICULARIS, Morris. Ibid., p. 174. 

1863. GRTPH.SEA VESICULARIS, K. E. SchafMutl. Siid-Bayerns Lethsea Geogn., 

p. 143, pi. xli, figs. 5, 6. 

— OsTREA VESICULARIS, A. V. Strombech. Zeitschr. d. deutsch. geol. Gesellsch., 

vol. XV, pp. 127, 1-37. 

1864. — VESICULOSA, 8. P. Woodward. Geol. Mag., vol. i, p. 112, pi. v, 

fig. 6. 

1865. — VNCisEh-LA, A. Leymerie. Bull. Soc. gcol. de France, ser. 2, vol. xxii, 

p. 367. 

1866. — (Gryph.*:a) vesicularis, K. A. Zittel. Bivalv. d. Gosaugeb. 

(Denkschr. Akad. Wissensch. Wien, Math.-nat. CI., 
vol. XXV, pt. ii), p. 123 [47], pi. xix, fig. 6 (? j>arf//»). 

1867. — VESICULARIS, B. Luiidgren. Palaeont. lakttag. Filxekalk. Liniluuan, 

p. 23. 
? — — — O. Fraas. Aus dem Orient, i, p. 88. 

? 1863. — HIPPOPODIUM, E. Eichimld. Lethsea Rossica, vol. ii, p. 3f7, 

pi. xix, fig. 5. 

— GRYPHJiiA VESICULARIS, Eichwcdd. Ibid., p. 394. 



OSTREA. 3G:i 

1869. OsTBEA VESiciTLARis, H. Cuquaiid. Mon. Ostrea, Terr. Cn't., p. 35, pi. xiii, 

figs. 2—10. 

— — HIPPOPODIUM, Coqiiand. Ibid., p. 100, pi. xviii, figs. 1, 4, .^> ; pi. .\ix ; 

pi. XX, tigs. 1 — 8. 

— — Lestjetjri, Coquaud. Ibid., p. 146, j)!. xli, figs. 1—4. 

— — PROBOSCIDBA, Coqwand. IhU.. p. 72, pi. xv, fig. 10 ; pi. xvi, figs. 

1 — 12 ; pi. xviii, figs. 1 — 5. 
_ _ vEsicuLARis, E. Favre. Moll. Foss. de Lemberg, p. 160. 

— — HIPPOPODIUM, Favre. Ibid., p. 161. 

1870. — — F. Bonier. Geol. v. Oberschles., p. 315, pi. xxxvii, 

fig. 7. 

— — VESICULARIS, H. Credner. Zeitschr. d. deutscli. geol. Gesellsch., 

vol. xxii, p. 225. 
_ _ _ C. Schliiter. Neues Jahrb. fiir Min., etc., p. 952. 

1871. G-RYPHaiA VESICULARIS, F. StoUczka. Palseont. Indica, Cret. Fauna S. India, 

vol. iii, p. 465, pi. xlii, figs. 2 — 4; pi. 
xliii, fig. 1 ; pi. xlv, figs. 7 — 12. 

1872. Ostrea hippopodium, H. B. Geinitz. Das Elbtbalgeb. in Sauhsen (Pal- 

fflontographiea, vol. xx, pt. 1), p. 177, pl.xxxix, 
figs. 12—27 ; pi. xl, figs. 1—3 ; pt. 2, pi. viii, 
figs. 5—7. 

1873. — VESICULARIS, /. I. LaJmsen. Foss. White Chalk of Simbirsk (Imp. 

Euss. Miu. Corps Instit.), pt. 2, 
p. 249. 

— var. JUDAicA, L. Lartet. Auual. Sci. geol, vol. iii, 

p. 69, pi. xi, figs. 8—10. 

187.5. — A. J. Jukes-Browne. Quart. Jouru. Geol. Soc, vol. 

xxxi, p. 295 (partim). 
? 1876. Gryph.«:a vesicularis (?), F. B. Meek. Invert. Cret. and Tert. Foss. U. 

Missouri, p. 20, pi. xi, fig. 2 ; pi. xvi, fig. 8. 

Ostrea hippopodium, D. Braiins. Zeitschr. f. d. ges.immt. Naturwiss., ' 

vol. xlvi, p. 394. 

1877. — A.Frifsch. Stud. imGeb. bijhmisch. Kreideformat., 

ii, Weisseuberg. u. Malnitz. Sohicht., 
p. 140, fig. 137. 
y 1878. — VESICULARIS, 0. Fraas. Aus dem Orient, ii, p. 86. 

— J. de C. Sowerbij, in F. DLron. Geol. Sussex, ed. 2, 

p. 386, pi. xxvii, fig. 3, 
— PvcNODONTA VESICULARIS, E. BaijJe. Explic. Cai-te geol. France, vol. iv. 

Atlas, pt. 1, pi. cxxxv, figs. 1 — 7. 

— proboscidea, Bayle. Ibid., pi. cxxxvi, figs. 1, 2. 

Ostrea hippopodium, C Barrois. Ann. Soc. gtol. Nord, vol. v, p. 407. 

— G. Behrens. Zeitschr. d. deutsch. geol. Gesellscb., 

vol. XXX, p. 260. 
1881. AvicuLA filata, R. Etheridge, in Penning and Jukes-Browne. Geol. Cam- 
bridge, p. 144, pi. ii, fig. 3. 
? 1882. Ostrea c/*. HIPPOPODIUM, If. iriHf/m.J/Ze)-. Jahrb. d. k. preuss. geol. Landes- 

aiist., fiir 1881, p. 29. 



564 CRETACEOUS LAMELLIBRANCHIA. 

1882. Gkyphjea vesicitlaris, H. Schi-mh-r. Zeitschr. d. deutsch. geol. Gesellscb., 

vol. xxxiv, p. 259. 

— O.STREA HiPPOPODiUM, Schrikler. Ibid., p. 269. 

1383. — __ yl. Fritach. Stud, im Geb. buhmiscli. Kreidefonnat., 

iii, Isersehicht., p. 122, fig. 98. 

1884. Grtph.ba vesicularis, C. A. W/iitf. 4tli Aun. Eep. TJ. S. Geol. Survey, 

p. 303, pi. xlviii, figs. 1 — 5. 

1885. — — K. P. Whitfield. Bracli. aud Lamellibr. Raritau Clays 

(Mon. U. S. Geol. Surv., vol. ix), p. 36, pi. iii, 
figs. 15, 16; pi. iv, figs. 1 — 3; pi. v. 

1888. — — G. MiiUer. Jalirb. d. k. preuss. geol. Laudesanst., 

fur 1887, p. 401. 

— OsTREA vesicularis, A. Peroii. Hist. Terr. Craie S.E. Bassiu Auglo- 

Parisien, p. 179. 

1889. — (Geyphjea) vesicularis, 0. Griepenkerl. Palseout. Abliaudl., vol. 

iv, p. 37. 
_ — HIPPOPODIUM, E. Hohajpfel. Die Mollusk. Aacheu Kreide 

( Palaeontographiea, vol. xxxv), 
p. 252, pi. xxix, figs. 3 — 7. 

— Gryph.*:a vesicularis, HoJzapfel Ibid., p. 253, pi. xxix, figs. 1, 2. 

1890. — — M. Blanckenliorn. Beitr. Geol. Syrieus, p. 75. 
1890-91. OsTREA HIPPOPODIUM, A. Peroii. Bracliiopodes etc., Terr. Civt. Hauts- 

Platoaux de la Tuuisie, p. 152. 
— — VESICULARIS, Peroii. Ibid., p. 175. 

? 1891. Gryph.«a VESICULARIS, J. Bolim. Paleeoutograpliica, vol. xxxviii, p. 91, 

pi. iv, fig. 3. 

— OsTEEA HIPPOPODIUM, BoJim. Ibid., p. 92, pi. iv, fig. 12. 

1892. — E- Stolley. Mittheil. a. d. Miii. lustitut. Univ. Kiel, 

vol. i, p. 235. 

— Gryph^ea VESICULARIS, Stollei/. Ibid., p. 236. 

OsTREA VESICULARIS, F. Vogel. Verhaiidl. nat. Vercius preuss. KheiuL, 

vol. xlix, p. 51. 

1894. — — A. Hennig. Geol. Foreu. i Stockholm Forliautll., 

vol. xvi, p. 513. 

— — HIPPOPODIUM, Hennuj. Ibid., p. 514. 

._ — VESICULARIS, J5. imifZ^rcH. MoWns^AMammiUatusodiMucronafa 

zouema, p. 35. 

— — HIPPOPODIUM, Liuulgren. Ibid., p. 36. 

1895. — (Gryph.ea) VESICULARIS, F. Vi>gel. HoUiiudiseh. Kreide, p. 7. 

— — HIPPOPODIUM, Vogel. Ibid., p. 7. 

(Grypji^a) HIPPOPODIUM, E. Tiessen. Zeitsclir. d. <leutsfli. geol. 

Gesellsch., vol. xlvii, p. 464. 

? Geyph^a VESICULARIS, /. i'"". T7/((<ertyecS. Trans. Roy. Soc. Canada, ser. 2, 

vol. i, IX 120. 
1897. OsTREA HIPPOPODIUM, A. Heniiig. llevis. Lamellibr. Nilssou's " Petrif. 

Suecana," p. 6. pi. i, figs. 1—6, 8, 9. 

— VESICULARIS, Hell nig. Ibid., p. 18. 

HIPPOPODIUM, R. Leonard. Palaeontographiea, vol. xliv, p. 51. 



OSTREA. 365 

1897. Grtph^ea vesiculaeis, F. NotUny. U. Cret. (Maestrichtian) Mari Hills 

(Palaeont. ludica, ser. xvi, vol. i), 
p. 39, pi. X, figs. 1, 2. 

— OsTREA VESicuLAEi.s, A. Rutot. Bull. Soc. Beige Gl'oI. Pal. et Hyclrol., vol. 

X, p. 26. 

— — HIPPOPODITJM, Butot. Ibid., p. 2t). 

1898. — — G. Mailer. Molhiskoufauna Uutersen. v. Eraun- 

scliweig u. Ilsede, p. 14, pi. iii, figs. 
10—15; pi. iv, figs. 1, 2. 

1899. . — — G. de Alessandri. Paloeontogr. Italica, vol. iv, 

p. 200. 

— OsTREA HIPPOPODIUM, Alessaiidri. Ibid., p. 199. 

1900. OsTREA (Gryph.ea) VESiCTJLARis, C. jlfa7/er-£')//?(ai-. Eclogae Geol. Helvet., 

vol. vi, p. 121. 

1901. Gryph^a vesicularis, A. Wollemann. Jalirb. d. k. preuss. geol. Landes- 

aust., vol. xxi, p. 14. 

1901. Gryph^a VESICULAEIS, H. ImJcrller. Palasontograpliica, vol. xlviii, p. 40, 

pi. ii, figs. 2 — 4 ; pi. iii, figs. 7 — 9. 
1901-02. OsTREA (Ptcnodonta) vesiculaeis, p. C/i'v/a^ Faim. Cic't. Portugal, 

vol. i, ser. 3, p. 10:?, 
pi. ii, fig. 18. 

1902. Gryph.ea vesicularis, A. Wollemann. Liiiieburg. Kreide (Abhandl. d. k. 

preuss. geol. Landesanst., n.f., 
37), p. 52. 

— Ostrea hippopodidm, /. p. /. Eavn. Mollusk. i Danmarks Kridtafl. I. 

Lamellil)r., p. 114. 

— Gryph^a vesicularis, Bavn. Ibid., p. 116. 

— — — /. Wanner. Palseoutographica, vol. xxx (2), p. 

119, pi. xvii, figs. 10—12. 

— — — E. Bacqnr. Ibid., p. 188, pi. xxii, figs. 1, 2. 

— — — J. A. Taff. Chalk of S. W. Arkansas (22ud Aiiu. 

Rep. U.S. Geol. Surv., pt. iii), pis. 
1— Iii. 

1903. Ostrea vesicularis, B. Fortau. Bull. Inst. Egyptieu, scr. 4, vol. iv, p. 308. 
? — Gryph^a vesicularis, /. F. Whiteaves. Mesoz. Foss. (Geol. Sin-v. 

Canada), vol. i, p. 401. 

1904. Pycnodonta vesicularis, H. B<iin-!1U. Mission Scieut. en Perse par J. de 

Morgan, vol. iii, pt. 4, Pak'ont., 
p. 278, pi. xxxvi, fig. 23. 

1905. GRYPH.a;A vesicularis, T. Wecjner. Zeitsihr. d. deutsch. geol. Gesellscli., 

vol. Ivii, p. 184. 

— Ostrea vesicularis, A. D. Arkhangelsl-y. Ann. geol. min. Russie, vol. vii, 

pp. 190, 205, pi. iv, figs. 
1,2. 

1906. GRYPH.a:A vesicularis, E. Biise. Fauna Senon. Cardenas (Bol. Instit. 

geol. Mexico, No. 24), p. 49, pi. iv, 
figs. 1 — 3 ; pi. vii, fig. 2 ; pi. is, fig. 4 ; 
pi. xii, tig. 6. 

48 



366 CRETACEOUS LAMELLIBRAXCHIA. 

1906. OsTBEA (Gkyph^ea) vesiculaeis, M. Bnule and A. Thevenin. Auual. 

PaleoDt., vol. i, p. 49 [7], pi. ii, fig. 3. 
? — Gryphjsa vesicularis, /. Pefhii. PiilKontographica, vol. lii, p. 188, pi. 

xii, figs. 2, 3. 

1907. — coNVEXA, jS'. Weller. Cret. Pal. New Jersey, p. 451, pi. xlv. 

1910. — VESICULARIS, F. Freeh. Neues Jalirb. fiir Min., etc., i, p. (>, 

pi. ii, fig. 1 . 
? — - OsTREA VESicuL.^Ris, H. Bfiiygeii. Ibid., Bcil.-Baud xxx, p. 744. 

1911. — HippopoDiVM, A. FrifscJi. Stud, im Geb. bolimiscli. Kreideformat., 

Korvcaner Sehiclit., p. 48, fig. 217. 
'r — Gryphea vesicularis, M. E. Tcuh'tsz. Mitteil. Jabrb. uugarisch. geol. 

Reichsanst., vol. xix, p. 110, 
pi. iii, fig. 3. 

— Ostrea hippopodium, W. lioyala. Bull. luternat. Acad. Sci. Cracovie, 

p. 167. 

— — — K. Vogel von Falckenstein. ZeitscLr. d. doutseb. 

geol. Gesellsch., vol. 
Ixii, p. 558. 

— GrypHjEA vesiculaeis, v. Falckenstein . Ibid., j). 560. 

Non 1859. Ostrea vesiculaeis, T. Wiltshire. Red Chalk of Eugland (Geol. Assoc), 

p. 16, pi. ii, fig. 5. 

Di'.'icriptii.Di. — The left valve, when attached by only a very small part of the 
vimljo, has a grypheate form, being nsnally very convex, and with the umbo 
prominent and incurved ; the outline of the valve is rounded, but the posterior 
part is more or less produced ; the postero-dorsal part is often convex and some- 
times distinctly limited from the remainder of the valve ; this convex part when 
strongly developed may be produced backwards in a wing-like form. In large 
specimens of the grypheate form this valve becomes very thick. 

When the left valve is attached to a larger .surface of more or less rounded 
outline it is still grypheate in form, but with the umboual region truncated owing 
to the attached surface being flat or concave. When the attached surface is still 
larger, relatively to the entire shell, the free marginal part possesses the same 
character as the corresponding part of the grypheate form, and this free part 
grows upwards from the attached surface. When nearly all the valve is attached 
then only a narrow rim grows upwards at the margin; lastly, in some cases the 
entire valve is attached so that the whole of it is flat or concave ; in the interior 
of such forms a few distinct concentric ridges are often found at intervals, and 
from the outermost of these the marginal part of the valve becomes gradually 
thinner and usually shows a porous structure. 

^\'lien the left valve is attached to a cylindrical or other elongate object, the 
form of the shell depends on the direction of the long axis of the attached surface. 
If the axis is nearly perpendicular to or forms a considerable angle with the plane 



OSTREA. 



•667 




143 



■^^;-2Mi« 



\k^^ 



f' 



f 






'.r 



< 



FlQS. 143-153.— Osirea vesicularis. Lam. HS-l-to. Upper Grc'ens;md (zone of P. asper), Warminster. 
Museum of Practical Geology, Nos. 259-18, 25<).50. US, left valve. l-H, right valve. 145. anterior 
view of 144 showing hoth valves. 14(i. Zone of ilicraster coi-niif/iiiHioii, 'Witheringtou, Dr. 
Blackmore's Collection. Interior of left valve. 147. Zone of Aciinocamax quudratus. East 
Hamham. Same Collection, liight valve. The left valve is entirely attached to the convex 
surface of an echinoid. 148, 14!). Zone of ^^craster cor-anfiuiniini, Graveisend. Hritish Museum, 
No. L. 20991. Exterior and interior of a left valve. l."jtAl53. Zone of BeUmnilclla murronata, 
Norwich. 150, right valve, Britisli Museum, No. L. 20616. 151, Dorsal view of l.JO showing both 
valves ; the left valve entirely attached to a nearly flat surface. 152, 153. Sedgwick Museum. 
Left and right valves. 146, 14", natural size. Otlier figures x J. 



:5(i8 CRETACEOUS T.AMELEIBRANCHIA. 

(iF the valves the left valve becomes convex; if the axis is more or less parallel to 
the ]ilaiie of the valves and to the hinge-line the left valve is less convex; and if 
in such cases the attached surface is mainly in front of the umlx) then the anterior 
part of the shell becomes elongated, whereas, when the attached surface is mainly 
posterior to the umbo the posterior part of the shell become elongated and the 
shell more inequilateral ; if the long axis of the attached surface extends from the 
umbo in a postero-ventral direction the shell becomes oljlique and very inecjui- 
hiteral. Occasionally the left valve shows two surfaces of attachment, one at the 
uiul)o, the other at some distance from it. Since the direction of growth depends 
mainly on the position of the attached surface, it is obvious that the relative length 
and height will be determined in the same way. 

The surface of the free part of the left valve is smooth except for growth- 
lines. The form and direction of the umbo, area and ligament-pit depend on the 
mode of attachment. The ai-ea is either nearly parallel to the attached surface or 
slopes gently from the hinge-line to the umbo, and consequenth' in the grypheate 
forms it eventually l)ecomes more or less nearly perpendicular to the plane of the 
valves of the adult shell, ])ut in completel}' attached forms the area and ligament- 
pit remain nearly parallel to the plane of the valves ; between these two extremes 
every gradation can be traced. The ligament-pit and the nmbo may curve 
forwards or backwards, or be perpendicular to the hinge-line. Small, irregular, 
rouiideil ridges or crenulations, more or less nearly at right angles to the margin 
of tilt' valve, are seen on the inside of the shell on each side of the area, but are 
most developed on the posterior side. The adductor impression is rounded or 
slightly oval. 

The ri(j]tt valve in the grypheate form with a very small attached surface is 
almost entirely concave or sometimes nearly flat. The part of the right valve 
w hieh corresponds to the attached part of the left valve is more or less convex, 
and repioduces the detailed markings as well as the general form of the attached 
surface ; when the latter is flat the corresponding part of the right valve is only 
slightly convex, and its convexity increases with that of the attached surface. As 
soon as the left valve grows free from the attached bodj^ the corresponding part of 
the right valve becomes concave and grows upwards at a considerable angle with 
the earlier convex part. When the entire left valve is attached the whole of the 
i-ight valve is slightly convex and there is no upward growth of the marginal part. 
When th(> outer layer of the right valve is well pi'eserved fine thread-like radial 
ribs are seen ; they are widely separated and cither straight or slightly irregular. 
The inner margin near the area has small ridges like those of the left valve. 

J//i/((7u'fe'. — The study of a large series of specimens shows clearly that Osfnui 
hippopodlum, Nilsson, is only a form of 0. vcniciil<iris in which the entire or almost 
the entire surface of the left valve is attached, and consecjuently that valve is 



OSTREA. 



:](39 




Ficis. lol-ltu .—Os/rea vesicularis, Lam. Zone of Be!enini<e/(rt nii(ci-oiia(a, Norwich. St-dgwick Museum. 
Cauiliiidfje ; except 15G, 157, in Dr. Kowe's collection. 1.54, 156, 159, 161, lO:!, Kit, 166, left 
valves. ° 155, right valve of 154. 157, right valve of 1.56. 158, interior of a right valve 
similar to 157. " IW", right valve of 15'J. 162, right valve of 161. 165, right valve of 164. 
167, dorsal view of 166. 166 and 167, natural size. Other figures x J. 



370 CRETACEOUS LAMELLIBRANCHIA. 

either nearly flat (fig. 151) or grows upward near the margin only (fig. l-i5), 
and the right valve is either slightly convex thi'oughout (figs. 147, 150) or with 
a narrow marginal part growing upwards (fig. 155). Although this type differs 
greatly in appearance from the grypheate form (fig. 182), yet every stage between 
the two extremes can be seen since there is a complete gradation from forms in 
which the entii'e surface is attached to forms in which only a ver^' small jmrt of 
the umbo is fixed. But whatever the form of the shell the part, if any, Avhich 
grows free shows similar characters. This view of the relationship of (>. hijijxi- 
/>ii(Iinni. and 0. rcsiciihrris has already been maintained by Peroii (IS'.)O) and by 
Miiller (18U8). 

In the Chalk of this country numerous examples of the left valve of an oyster 
attached completely to flat or convex objects are found and have been commonly 
referred to 0. Normaniana, d'Orbigny^ (fig. 146). The right valve is nearly always 
missing. The marginal part of the left valve thins away rapidly to a sharp edge 
and this part usually shows a porous structure, whilst on the inner part of the 
valve a few distinct concentric ridges are seen ; some of these specimens are young 
individuals and many are probably immature ; the concentric ridges probably 
indicate the beginning of an upward growth of the margin which was soon dis- 
continued and the attached growth resumed. Similar concentric ridges are present 
in some undoubted examples of 0. ve.iicnlaris (figs. 148, 149), and the identity of 
this form with 0. venculavlti is proved by the occasional preservation in its original 
position of the right valve (Plate LV, fig. 4; text-fig. 147) showing the charac- 
teristic radial ornamentation of 0. vesicularis. A left valve of this form is figured 
by Geinitz" as 0. Inppoj^o'Uum. 

Avicula filatn, Etheridge, from the Totternhoe Stone (zone of Holaster snb- 
globosns) of Burwell, is founded on a right valve of a small specimen of 0. vesicx- 
laris, and shows clearly the fine radial ribs. It agrees with small specimens 
attached throughout or with only the margin free, found in the Upper and Lower 
Chalk as well as in the Gault^ (Plate LV, figs. 4, 5, 7 ; text-fig. 147). 

0. clavata, Nilsson, is a form in which the posterior part is more produced than 
usual owing to the position of the attached surface. 

The liippopodinm form of 0. vesicularia found in the Cenomanian Avas named 
0. Leftncnr'i by d'Orbigny on account of its lower horizon. But Hennig, who has 
studied a series of Cenomanian specimens, sees no reason for separating it from 
the Senonian examples, and Miiller (1898) likewise includes it in 0. ro^icuhtrh. 

• ' Pal. Frau9. Terr. Cn't.,' vol. iii (1847), p. 746, pi. cccclxxxviii, figs. I— 3. 

- • Palseoutogriqiliica,' vol. xx, pt. 2, pi. viii, fig. 6. 

^ Anomia mihrailiata, Eeuss, is probably a small fxam^jle of 0. rcslnilarif similar to Avicula 
Jilala of Etheridge. Eeuss, 'Die Versteiu. der biihm. Kreideformat.,' pt. 2 (1846), p. 45, jjI. x.\xi, 
fig. 19. 



OSTREA. 



371 




180 



Figs. KiS-lSl. —Osfroa vesicnlaris, Lam. Zone of lichnmitella mi(rcoiia/rt, Noi'wicli. 10S>, Iti'.l, left ami 
riflht valve.s. Norwich Museum, No. 2133. 170, 171, left and light valves. Dr. Kowe's Collection. 
172, 173, left and right valves. Sedgwick Museum. 171-, 17.5, left and right valves. Norwich 
Museum. 17G-179, left valves. Sedgwick Museum. 178, posterior view of 177. ISO, 181, left 
valve. Dr. Kowe's Collection. 181, anterior view of 180. All x J. 



372 CRETACEOUS LMIELLIBRAXCHIA. 

0. prohosddra, d'Arcliiac, is included b}' Zittel and by G. Midler in 0. vesiadaris, 
and the latter points out its probable close connection with 0. biatn-ictilata, 
Lamarck. The type of 0. prohosciilea from the Santonian of Saintes, Dordogne, is 
not quite satisfactory, but most of the specimens figured by Coquand seem to be 
inseparable from 0. vesiciilnris. 

The grypheate forms of 0. vpakiilariA have been usually placed in the " genus " 
Clri/ph.va, and the hippopodutm forms in Odrea; in the case of this species, at any 
rate, " Gri/phssa " canrwat be accepted as a genus. ^ 

In the Lower Chalk (Plate LV, figs. 8, 9) a small grypheate form" varying 
only to a small extent in dimensions is common and is not usually associated with 
larger forms ; the uniformity in size and character of this form at first give the 
impression that it may be a distinct variety, but comparison with the small forms 
of 0. vesicularis from the Upper Chalk (figs. 166, 1G7) shows that they cannot be 
separated ; their small size was probably due to local conditions. Further, it may 
be noted that in earlier beds (the Upper Greensand) large forms of butli the 
grypheate and hippopocUum types occur (figs. 143 — 145), and are indistinguishable 
from those found in the Upper Chalk. Some rather small grj'pheate forms are also 
found in the Gault and Cambridge Greensand, and also forms with all or the larger 
part of the left valve attached, but they are not common in the Gault. 

A few specimens of a small oyster have been found in the Lower Greensand of 
Atherfield and Shanklin, and show the fine radial ribs on the right valve^ ; some 
of these, and probably all, are examples of 0. rcsinthtri^:, but the left valves are 
not, in all cases, well preserved.* 

Remarks. — 0. veundaris attains its greatest development in the zones of 
BeJemnitdla vmcronala and Ostrea lunata in this country, Avhere the grjqjheate 
forms are abundant and reach a large size. The form with the posterior wing- 
like projection (figs. 174-179) occurs mainly in the zone of 7)'. mncronatn. 0. /•",>■/- 
cularis has been observed attached to sponges, corals, echinoids, oysters, Iiioceramus, 
Spondi/lus, gasteropods. Ammonites, and Belemnitella. The long range in time 
and the wide geographical distribution of this species have already been noted by 
Hennig and other authors. 

Tiipps. — 0. vesmdari.i, Lamarck, and 0. ddtoide.a, Lamarck, from the Upper 
Chalk of Men don. Gri/phsea globo.m, Sowerby, from the zone of Belemnitella 

' Tliis conclusion is in agreement with Peron's views on the " genera " of the Ostreidfe ; see 
' Descript. Bracli., etc., Terr. Cret. Tunisie' (1890—111), pp. 107—109. 

2 A similar but rather larger form occurs in the Melbourn Eock and [Aen Ms-niarls. 

' Examples of this are figm-ed in vol. i, pi. v, figs. 4, 6 

■* Ostrea vinjafa, Sowerby, possesses numerous fine radial ribs. The type is the only specimen 
known ; it was found in the Lower Chalk (probably zone of Holaster gubglohosus) of Sussex. The 
aflSnities of this form cannot be determined. Dixon, ' Geol. Sussex ' (1850), p. 357, pi. xxvii, fig. 1. 



OSTRBA. 



0{- 



umcronata of Norwich, is in the British Museum. 0. hippopodlnm, Nilsson, from 
the Upper Chalk of Kopingc, is in the Lund ]\Iuscuin. The specimens of 0. hippo- 
jjudiuiu figured by Goldfuss from the Cenomanian of Ussen, are in the Munich 
Museum. The examples of 0. vesicular i.i figured by William Smith came from 
Norwich and are in the British Museum. Tlie original of (hijplixa (jlohosa var. 
depressa, Sowerby (in Dixon), cannot be found ; the specimens of O.S'frea figured by 
the same author (Dixon, pi. xxviii, figs. 22, 23), from the zone of Holastersuhgloho.^iis 
near Warminster, are in the British ]\luseum. The specimen figured by S. P. 
Woodward as 0. vesiculosa from the Upper Chalk of Sussex, is also in that Museum. 
Acicula filata, Etheridge, from the Totternhoe Stone of Burwell, is in the Sedgwick 
Museum. 




Fio. 182. — Osd-ea fc»'icK?aris, Lam. Zone of Osfrea ZunaJa, Triminghani. Dr. Rowe's Collection. Left 

valve. X J. 



Distiihntion. — Lower Greensand (Ferruginous Sands) of Shanklin. Gault of 
Folkestone. Cambridge Greensand. Upper Greensand (zone of Schlmnbachia 
rostrata) of the Isle of Wight. Upper Greensand (zone of Pecten aspcr) of War- 
min.ster. 

Chalk Marl (zone of SrhhenJiarida rarians) of Folkestone, Offham, and Burwell. 
Cenomanian (Meyer's bed 11) of Beer Head. Cenomanian Sandstone of 
Wilmington. 

Zone of Holaster suhijlohosus of Chilcomb (IIant.s), Glynde (Lewes), Burham, 
Arlesey, Ickleford (near Hitchin), Cheri-y Hinton, Burwell, and Isleham. 

Zone of Rhi/iichonelli Gavieri of the South Devon coast and Dover. Melbourn 
Rock, ^lelbourn. 

49 



374 CRETACEOUS LA:\1ELLIBRAXCTII.\. 

Zone of 'I'cn'bratiiliiKi laid of the South Devon coast, Dover, Cnxtoii, Charing, 
and Beachy Head. 

Zone of Hola.tter flniinH of Mujae Baj', Borstal, "West Wratting, Cheveley, and 
Swaffham (Norfolk). 

Zone of MirrdKfrr cor-tedndmarinmoi Borstal Manor, Chatham, and Stevenage. 

Zone of Micrnster cnr-augulmtin of Witherington, Qnidliiiinpton, Cnni]) Hill 
(near Salisbury), Northfleet, Gravesend, and the Thanet coast. 

Zone of Marsvjntos fcfitudinarmH of the Thanet coast. TJiiiiiirriinis l)an(l of 
Devizes Road (Salisbuiy). 

Zone of AcH'iKinima.v. i[i(ailrntiii< of "Whaddon, East and West Haruhani, Fareham, 
Shawford, and Bishops Waltham. 

Zone of Belemnitclln mucrondta of the Dorset coast and Norwich. 

Zone of Ostrea Innnta of Trimingham. 



OsTKKA VESiciu.osA {Suicerhi/), 1822. Plate LV, figs. lU— 11; Plate LVI, fig. 1. 

1822. Gryph^a vesiculosa, J. Soirei-bi/. Min. C'oiu-li., vol. iv, p. 9-], [.I. ccc-l.\ix. 
? 1847. OsTREA VASCULUM, A. (VArcliiac. Mrm. Soc. f;i'ol. de France, ser. 2, vol. ii, 

1>. 312, pi. xvi, figs. 5, 6. 
184:fl. Grypha:a vesiculosa, T. Brown. Illustr. Foss. Couch. Gt. Brit, ami 

Ireland, p. 149, pi. Ixi, figs. 8, 9. 
18.50. OsTREA VESICULOSA, E. Gurvanger. Bull. Soc. ffcol. de Frauce, ser. 2, 

vol. vii, p. 802. 
1854. Gryph.s:a vesiculosa,/. Morris. Cat. Brit. Foss., ed. 2, p. 168. 
? 1868. Ostrea columba, A. Briart and F. L. Corvef. Meule de Bracqiiegnies 

(Mem. cour. et Mem. des Sav. etrangcrs, vol. xxxiv), 
p. 46. pi. iv, figs. 1.3—15. 
1869. — vesiculosa, H. Coqnnnd. Hon. Ostrea, Terr. Cn't., p. 152, pi. lix, 

figs. 4—7. 
1871. — — F. J. Pictef and G. Camjnchc. Foss. Terr. Cn't. Ste. 

Croix (Maier. Fal. Suisse, ser. 5), p. 311, pi. exciv, 
figs. 1 — 6. 
— Gryph^.a vesiculosa, i^. S/o/ffz/i-ff. Palffiont. Indica, Cret. Fauna S. India, 

vdl. iii, p. 466, pi. xxxix, figs. 1, 2. 
1882. — — G. Segnenxn. Atti R. Accad. Lincei, ser. 3, CI. Sci. 

Fis. Math., vol. xii, p. 182, i)l. xix, fig. 2. 
1890-91. OsTRKA vesiculosa, a. Peron. Descript. Braeh., etc , Terr. Cn't. 'J'uuisie, 

p. 126. 
1903, — — Ii. Fortau. Bull. Inst. f;g_vptieu, ser. 4, vol. iv, p. 290. 

? 1908. GryphjEA ff/?'. VESICULOSA, f. Fai-re. Neues Jahrb. fiir Min., etc., Beil.-Bd. 

x.vv, p. 609. 

Non 1864. Ostrea vesiculosa, S. P. Woodward. Geol. Mag., vol. i. p. 112. i>l. v, fig. 6. 



OSTREA. 375 

DescripfioiL—Lah valve usually tliick, very convex, grypheate, more or less 
oval, height usually considerably greater than the length ; slightly or moderately 
ine(|uilateral, sometimes with a rounded ridge extending from the umbo to the 
postero-ventral extremity. Posterior part often convex and separated from the 
reiuainder of the valve l)y a furrow. Umbo sharp, prominent, more or le.ss 
incurved, and usually witli a small posterior curvature; surface of attachment 
generally small. Area and ligament-pit high, straight or with a small backward 
curvatui-e. Adductor impression oval or rounded. Right valve thin, concave. 
Surface of both valves smooth, except for growth-lines. 

Abilities. — This species is closely allied to 0. vesicularix, but the umbo is more 
pointed, usually less incurved and with a smaller attached surface; the area is 
higher, and usually the height of the shell is relatively greater in proportion to its 
length. Most of these differences are probably to be accounted for by the small 
size of the attached surface. 

Tiipe. — From the Upper Greensand of AVarininster, in the British Museum. 

DUtvibntiiin. — Upper Greensand : common in the zone of Scldoenhachia rostrata 
of Ventnor, Warminster, Dinton and Potterne; rare in the zone of Fcxti'ii nxpar 
of Ventnor, Warminster, and Ballard Down (Swanage). Chloritic Marl of 
Coinptou Bay, Isle of Wight. 



OsTKKA CAXALKULATA {Soivcrbi/), 181:5. Plate LVI, figs. 2-10. 

1813. Chama canaliculata, /. Soiiyrhi/. Miu. Conch., vol. i, p. 68, \>\. xxvi, tig. 1 

(uou Oslrea canaliculata, Sowerb}'.) 
1821. OsTREA CANALICULATA, M. J. L. Defiance. Diet. Sci. luit., vol. xxii, ]>. 26. 
18-27. OsTBEA LATERALIS, 5". Nilssoti. Petrific. Suecaua, p. 29, pi. vii, tigs. 7 — 10. 

— Chama conica, Nilsson. Ibid., p. 28, pi. viii, tig. 4. 

1829. Gryph.«a canaliculata, J. de C. Sowerhij. Miu. Couch., vol. vi, p. 218. 

— Exogyra undata, Sowerhy. Ibid., vol. vi, p. 220, pi. dcv, figs. 5 — 7. 
1833. OsTREA lateralis, a. GohlJ'uxx. Petref. Genu., vol. ii, p. 24, \A. Ixxxii, 

%. 1. 
y 1834. GRVPH.tiA VOMER, S . G . Mortoii. Synopsis Organic Remains Cret. U. States, 

p. 54, j>l. ix, fig. 5. 
1837. OsTREA LATERALIS, \V. HIkI ii(jei\ Letliaea Sueeica, p. 4ti, pi. xiii, fig. 1. 

— Ami'uiuonte undata, G. G. Punch. Polens Pahiout., ]>. 39. 

1842. Exogyra parvula, A. Leijmerie. Ml'iu. Soc. gc'ol. de France, ser. 2, vol. v, 

p. 17, pi. xii, figs. 8, 9. 
1845-6. OsTREA lateralis. If. B. Geinitz. Grundriss d. Versteiu., p. 480, pi. xx, 

fig. 22. 

1846. Exogyra laterali.s, A. E. Rcukk. Die Versteiu. der biihui. Kreideforuiat., 

pt. 2, p. 42, pi. xxvii, figs. 38 — 47. 

1847. Ostrea canaliculata, .1. il'Orhiijuij. I'al. Franc. Terr. Crct., vol. iii, 

]<. 709, pi. cccclxxi, figs. 4—8. 



:!?(; CRETACEOUS LAMEF.LIHHANCHIA. 

1847. ExoGYRA LATEitALrs, J. Muller. Petref. der Aacbeu. Kreidof., j)t. 1, p. 40. 

1849. Gryph«a undata, T. Brovn. Illu.str. Foss. Conch., 6t Britain 

and Ireland, p. 149, pi Ix, fis^s. 14. 1.5. 

— — canaliculata, Brown. Ibid , p. 149, pl. Ixi, lig. 18. 

1850. OsTEEA canaliculata, a. <VOrhi(jny. Prodr. de Pal., vol. ii, pp. 139, 170, 

2.55. 
? 1852. — CTRToMA, E. Kiier. Deukschr. Akad. Wissenseh. Wieu , Matli.- 

iiat. CI., vol. iii, p. 820, p!. xvii, fig. 11. 

1853. — CANALICULATA, F. J. Flcli't 1111(1 W. Rovx. MoU. Foss. Gres verts 

de Geneve, p. 522, 
pl. 1, fig. 2. 

1854. — — J. M<.r)ii<. Cat. Brit. Foss., ed. 2, p. 173. 

EXOGYEA LATERALIS, jJ/orriV. Ibid., p. I(i7. 

1863. OsTREA LATERALIS, A. V. Stromheclc. Zcitschr. d. deutsch. gcol. Gt'sellscli., 

vol. XV, p. 110. 

— ExoGTRA LATERALIS, H. Breschef. Ibid., vol. xv, p. 357. 

1867. OsTREA L.VTERALis, B. LmHhjreu. Palteont. lakttag. Fiixekalk. Liniliamn. 

p. 23. 

1868. ExoGYRA LATERALIS, E. Eicliwahl. Letlisea Rossica, vol. ii, p. 398. 

1869. OsTREA CANALICULATA, //. Ciiquciiid. Mou. Ostiea, Terr. Crt't., p. 128, 

pl. xlv, figs. 13, 14; pl. xlvii, 
figs. 7—10; il, Iii. fig. l-i; pl. Ix. 
figs. 13—15. 
— • — LATERALIS, Coqiiaiid. Ibid., p. 96, pl. xviii, tig. 12 ; 1>1. xxx. 

figs. 10-14. 

1870. ExoGYRA LATERALIS, F. Bi'mcr. Geol. V. Oberschles., p. 341, jil. xxix. 

figs, 4, 5. 
? — OsTREA LATERALIS, H. Crechier. Zeitsflir. d. deutsch. geol. Gesellsch., 

vol. xxii, p. 228. 
1S71. — cxyxhicvLkTA, F.J. Picf el atid G. Cirm2>lc/ie. Foss. Terr. Cn't. Ste. 

Croix (Alater. Pal. 
Suisse, ser. 5), 
p. 305, pl. exeiii. 
figs. 4 — 14. 

— ExoGYRA CANALICULATA, F. Sloliczla. raltcont. ludica, Cret. Fauna S. 

India, vol. iii, p. 463, pl, xlviii. 
figs. 6—8. 
1872. OsTREA (Kxooyra) LATERALIS, H. B. Geitiitz. Das Elbthalgeb. in Sachsen 

(Palseontograpliica, vol. 
XX, pt. i), p. 179, i>l. xli. 
figs. 28—35 ; pt. ii, pl. 
viii, figs. 15 — 17. 
1877. ExoGYRA L.VTERALis, A. FfihcJi. Stud. iiu Geb. biJhmisch. Kreideforniat.. 

ii, Weissenberg. u. Malnitz. Schiclit., 
p. 140, fig. 136. 

1881. OsTREA LATERALIS, J. Gosselet. Esquisse geol. du Nord, pl. xvii, fig. 14. 

1882, ExoGYRA LATERALIS, H. Scliroder. Zoitsclir. d. deutsch. geol. Gesellsch.. 

vol. xxxiv, p. 261. 



OSTEEA. 37 r 

1882. ExooYKA cANALicuLATA, G. Setjiieiizd. Atti E. Accad. Lincei, ser. 3, CI. 

Sci. Fis. Math., vol. xii, p. 17G. 

1883. — LATERALIS, FrilKch. Op. cit., iii, Isersehicht., p. 118. 

? 1887. — rf. LATERALIS, F. Frcch. Zeitschr. d. deutsch. geol. Gesellsch., 

vol. xx.xix, p. 153. 

1888. OsTREA CANALicuLATA, A. Peroii. Hist. Terr, de C'l-aie S.E. Ba.s.sin 

Anglo-Parisien, p. 175. 

— ExoGTRA CANALICULATA, G. MUllcf. Jalirl). d. U. pivuss. geol. Landesanst. 

fill- 1887, p. 401. 

1889. ExoGVEA LATERALIS, FrlffcJi. Op. cit., iv, Teplitz. Sehifht., p. 86. 

— OsTREA (Exogyka) LATERALIS, O. Grirjffnkerl . Seuou v. Kouigslutter 

(Palaeout. Abbaudl.. 
vol. iv), p. 36. 

— ExoGYEA LATERALIS, E. Holzapfel. Die Mollu!,];. Aaclieu. Kveide (Pala;on- 

tographica, vol. xxxv), p 256. 
1890—91. OsTREA CANALICULATA, A. Pewii. Desciipt. Braehiop., etc., Terr. Cn't. 

Tunisie, p. 163. 

1893. ExoGTRA LATERALIS, Fritscli. Op. fit., PHeseii. Sfliicht., p. 102. 

1894. OsTREA LATERALIS, A. Hemiiy. Geol. Fiiren. i Stockliolm, ForbaiulL, 

vol. xvi, p. 513. 

1895. — (Exogyea) LATERALIS, F. To(jel . Hollandisch. Kreide, p. 13. 

'■ — ExoGYRA (■/". CANALICULATA, E. Tiegseit. Zsitsclir. d deutsfh. geul. 

Gesellsch., vol. xlvii, 
p. 465. 

1896. OsTEEA CANALICULATA, A. J. J tikt's-Brovne and W. Hill. Quart. Jourii. 

Geol. Soc, vol. 
Iii, p. 149. 

1897. — LATERALIS, A. Helm!,/. Eevision Lamellibr. i Nilssous 'Petrif. 

Sueeaua,' p. 23. 

— ExoGYRA LATERALIS, Fritscli. Op. cit., vi, Chlomek. Schicht., p. 68. 

— — — R- LeonhanJ. Palseonlographica, vol. xliv, p. .".0. 

— — —A. Rutot. Bull. Soc. Beige Geol. Pal. et Hvdml.. vol. x, 

p. 27. 

— — cAHAmcvLATA, B. B. Newton. Proe. Dorset Nat. Hist, and Antiq. 

Field Club, vol. xviii. p. 91, pi. 
iii, figs. 7, 8. 

1898. OsTEEA CANALICULATA, B . Foiidii. Bull. Inst. Egyptien, ser. 4, vol iv, 

p. 292. 

— Exogyea LATERALIS, G. Midler. Mollusk. Uuterseu. v. Brauusehweig u. 

Ilsede (Abhandl. d. k. preuss. geol. 
Landesanst., n.f., 25), p. 15, pi. iii. 
fig. 2. 

— — — 0. M. Eels. Geognost. Jahresh. (1897), p. 108. 
■^^^'- — — A. WvUemaini. Jahrb. d. k. preuss. geol. Landesanst.. 

vol. xxi, p. 14. 
— ^f Ii>d->'lli): Palseoiitographica, vol. xlviii, p. 38. 

1902. — — J P. J. Porn. Mollusk. i. Danniarks Kridtaflej. I. 

Lamellibr., p. 118. 



•i78 CRETACEOUS LAMELLIBRANX'HIA. 

1905. EsoGYRA LATERALIS, T. Wefjiier. Zeitschr. d. dcutsch. geol. GesoUsch., 

vol. Ivii, J). 184. 
? 1907. GRYPH.f;osTREA VOMER, S. Welh'r. Cret. Pal. New Jersey, p. 455, jil. xliv, 

figs. (5— 11. 
1909. OsTREA (Exogyra) lateralis, W. h'liijaUi. Bull. Internat. Acad. Sei. 

Craoovie (1909), 2, 
p. 691. 
1911. Exogyra lateralis, Frilnch. Oji. cit., Korycau. Schiclit., p. 46, fig. 210. 
— — — K. Voijel von Falclceiiste'in. Zti'itschr. d. deutseb. geol. 

Gesellsch., vol. Ixii, 
]i. 561. 

Deiicription. — Shell generally rather small, usually higher than long, very 
inequivalve. 

Left valve very convex or inflated ; the greatest convexity is between the 
umbo and tlie postero-ventral extremity, and gives in some ca.ses the appearance 
of a much rounded carina, l)ehind which the valve is either flattened or slightly 
concave; sometimes there is a posterior "wing-like expau.sion. The ventral 
margin is rounded ; the lower part of the posterior margin is often slightly 
concave, ending above in a point. Umbo usually much incurved, and dii-ected 
posteriorly. The ligament pit usually curves posteriorly. This valve is attached 
posteriorly to the umljo ; the size, shape, and direction of the attached surface 
vary in different individuals, and affect the form of the shell in the usual 
way. The surface of the shell shows growtli-lines, and in some specimens 
tliere are numerous, fine, somewhat irregular ridges running pai'allel to the 
margin of the valve. In the interior of the valve a few widely separated growth- 
ridges occur. 

Right valve operculiform, nearly flat, or concave or undulating. Umbo very 
small, curving spirally forwards. Surface with widely separated ridges running 
parallel to the margin of the valve. 

A^iiitic'a.—Tlui Albian and Cenomanian examples of this species were regarded 
by Co([uand as distinct from those found in the Upper Chalk and named 0. J(dernlis 
by Nilssou; but d'Orbigny, Geinitz, Peron, Jukes-Browne, and Heunig have 
shown that the forms named In feral Ik cannot be separated from those which occur 
in earlier beds {riiiKilicnlata). Peron states that on the Continent this species 
I'anges without interruption through all the stages of the Cretaceous, from the 
Aptian to the Danian; he also notes its wide geographical distribution. This 
species belongs to Conrad's '• genus " G nj phxostrea ; it has been referred to 
(rvijphxd, by some writers, but more usually to E.vogi/ra ; the left valve, except for 
the attached surface, is often grypheate in form, while the right valve shows some 
resemblance to E.coyijni. Pictet and Campiche consider that 0. canaliculatn is 
closely related to Exuijijra conlca; but it seems more probable that it is allied to 



OSTREA. :57'.> 

0. veskularls, the differences being accounted for by tlie attached surface in the 
former being on the posterior side of the shell. 

The form with well-developed concentric ridges (Plate LVI, fig. ]0), which 
is abundant in the zone of Actlnor.amnx quadratns, but ranges from the zone of 
Rhi/nclionella Cavieri to that of Belnuiiitdht miicrdiuifd, has been named 0. canalini- 
laia vai'. Kfrinta} 

Tijpc'i. — Cliama canal inilata, Sowerby, from the Upper Greensand of Shute, 
near Warminster, is in tlie British Museum. 0. Ifitcralis, Nilsson, is from the 
Upper Chalk of Sweden. Gliama conica, Nilsson, from the Upper Chalk of 
Kopinge, Sweden. Exoyijra nndata, Sowerby, from the Upper Greensand, 
Blackdown, cannot be found. 

Distribution. — Hj'the Beds (Bargate Stone) of Godalming. Lower Greensand 
of Faringdon and Brickhill. 

Gault of Folkestone and Okeford Fitzpaine. Upper Greensand (zones of 
SrhhruJjachia roffnita and Foctcn nxpnr) of the Isle of "Wight (Ventnor, Xiton, 
Compton Bay). Upper Greensand (zone of SchlferiJmclna rostrata) of Blackdown. 
Upper Greensand (Rye Hill Sands) of Warminster. 

Chalk ]Marl (zone of Sclila'iiIiarJiia varictnx) of Chiseldon. Cenomanian of 
Wilmington, Devon. Zone of Holaster suliglnljosus of Fulbourn and Burwell. 

Zone of RJn/nchouella Cuvieri of Harvet (Kent). Melbourn Rock of Hitchin. 

Zone of Tcrehratiilina lata of Hampshire, the South Devon coast, and Dover. 

Zone of Holaster planus of Culver Cliff and Dover. 

Zone of Micraster cor-testudinarinm of Pinhay, Borstal, Seaford and Dover. 

Zone of Micraster cor-ancjuinum of Quidhamptom and Northfield. 

Zone of Marsupites testudinariu^ of Taplow. Uintacrinns band of Devizes, 
Road (Salisbury), Holmwood Park (Keston), and the Thanet Coast. 

Zone of Actiiiocama.v qundrafus of East and West Harnham, Whaddon, Marwell 
(Hants), Compton, Shawford, Fareham, West Meon, Mottisfont, Taplow and 
Brighton. 

Zone of Belemuitrlla unicrouafa of the Dorset Coast, Rogers Whiting Pit 
(Fareham) and Alderbury well. 

Zone of Ostrea hnmlii of Triniingliam. 

OsTREA SEMirr.AXA, J.de C. Sovy-rhi/, lc?2"). Plate T.VI, figs. 17— 11». Plate LVII. 
Plate LVIII, figs. 1—5. Text-figures 183—193). 

1803. OsTRACiTEs srr.cATrs, /. F. Blinnenbarh. Specini. art-hseol. tell., p. 18, pi. i. 

fig. 3. (N<,iu. Oflrea nulrata. Born, 
1778.) 

» Rowe, ' Zones of the White Chalk. I. Keut and Susse.v ' (1900), p. 34.5 ; Griffith and Biydone, 
' Zones of the Chalk in Hants ' (1911), p. 3. 



;380 CRETArKOUS LAMELLIBRANCHIA. 

1822. OsTREA, G. Mantell. Foss. S. Downs, p. 207, pi. xxv, fig. 4. 

1825. — SEMIPLANA, J. de C. Sowerby. Min. Couch., vol. v, p. 144. pi. 

cccel.vxxi.\, fig. 3. 
1827. — Ki.ABELLiFOEiMis, ,S'. NUssoH. Pctntic. Suecaua, p. 31, pi. vi, 

fig. 4. 

— — ? PLICATA, NihsoH. Ibid., p. 31, pi. vii, fig. 12. 

— — pusiLLA, ^i7(!8o?(. Ibid., p. 32,pl. vii, fig. 11. (Nouj;HSi7?«,Brocchi, 

1814.) 
1833. — AL^FORMis, S. Woodtrant. Geol. Norfolk, p. 48, pi. vi, figs. 

1—3. 

— — iNEQUicosTATA, Woodirard. Ibid., p. 48, pi. vi, fig. 4. 

— — FLABELLiFORJiis, A. Goldj'iiss. Petrcf. Germ., vol. ii, p. 12, pi. 

Ixxvi, fig. 1. 

— — SULCATA, Gold/uss. Ibid., p. 13, pi. Ixxvi, fig. 2. " 

— — ARMATA, Gold/uss. Ibid., p. 13, pl. Ixxvi, fig. 3. 

1837. — FLABELLiFOEMis, W. Hii'l iiijef. Letlisea Suecica, p. 48, pl. xiv, 

fig. 1. 

— — ? PLICATA, Higitiyi'i-. Ibid., p. 48, pl. xiv, fig. 2. 

1837. — INCONSTANS, F. Diijardui. Ml'ui. Soc. gi'ol. Je France, vol. ii, 

p. 229. 
1839. — FLABELLiFORMis, H. B. Gi/iiiitz. Char. d. Scliicht. u. IVtret'. 

des siiehs. Kreidegeb., \'t. 1, 
p. 19. 
1841. — — F. A. Ri'iiiter. Die Versknu. d. uord-deutsch. 

Kreidegeb., p. 45. 

— — SULCATA, Blimer. Ibid., p. 4f>. 

— — ARMATA, Rl'imer. Ibid., p. 46. 

? 1843. — MACROPTERA ? H. B. Geiiittz. Die Venstein. von Kieslingswalda, 

p. 17, pl. iii, figs. 22—24. 

— — SULCATA, Geinitz. Ibid., p. 17. 

1846. — — A. E. Iteuss. Die Verstein. der bijhm. Kreideforuiat., 

pt. 2, p. 39, pl. xxviii, figs. 2 — 4, 8. 

— — FLABELLIFORMIS, Eeuss. Ibid., p. 39, pl. xxviii, figs. 5 — 7, 16, pl. 

xxix, figs. 19, 20. 

1847. — SEMIPLANA, A. d'Orbiyny. Pal. Franc. Terr. Crct., vol. iii, p. 747, 

pl. cccclxxxviii, figs. 4, 5. 

— — FLABELLIFORMIS, ,7. Jl/iV/Zt')-. Pctref. dor Aaclicu. Kreidef.. pt. 1, 

p. 39. 

— — ARMATA, MiiUer. Ibid., p. 39. 

1849. — SEMIPLANA, T. J?*vj)(». Illustr. Foss. Conch. Gt. Britain and Irelan<l. 

p. 145, pl. lix, fig. 7. 

— — iN.EQUicosTATA, BfouH. Ibid., p. 147, pl. Ixi,*, fig. 13. 

1850. — SEMIPLANA, H. B. Geinitz. Das Quadersandst. oder Kreidegeb. in 

Deutschland, p. 198. 

— — CARiNATA, /. de C. Soiverby, in F. Dixon. Geol. Sussex, p. 357 (0. 

frons, p. 386, ed. 2), 
pl. xxvii, fig. 2. 

— — SEMIPLANA, A. d'Orbiijny. Prodr. de Pal., vol. ii, p. 256. 



OSTREA. 381 

?1850. OsTKEA SEMiPLANA, A. AUli. Greoga.-paliiout. Bescliroib. v. Lemlieri^ 

(HaiJini,'er"s Naturwiss. Abhaudl., vol. 
iii, pt. 2), p. 251, pi. xiii, fig. 2. 
1851. — Bronni, /. Jf/VWe?*. Petref. der Aac-heu. Kreidef., pt. 2. p. 09, pi. vi, 

tig. 20. 
1854. — SEMIPLANA, J. Morrii'. Cat. Brit. Foss., ed. 2, p. 17-t. 

— — iN.EQUicosTATA, Morris. Ibid., p. 173. 

1859. — SEMIPLANA, /. Mailer. Petref. der Aachen. Kreidef., Supplement, 

p. 7. 
1863. — — R. DrescJier. Zeitschr. der deutsch. geol. Gesell.scli., 

vol. XV, p. 356. 

SULCATA, A. KinllJl. lllld., vol. XV, p. 732. 

1868. — FLABELLiFOKMis, E. Eickwald. Letlisea Bossica, vol. ii, p. 368. 

1869. — tiEMivLAVX, H. Coqiiand. Mon. Ostrea, Teir. Cret.,p. 74, pi. xxviii, 

figs. 1—15; pi. XXXV, figs. 1, 2; pi. 
xxxviii, figs. 10 — 12. 

— — cuccLus, Coquaiid. Ibid., p. 52, pi. xvii, figs. 19 — 21. 

— — LiCHENiFORMis, Coqiiaiul. Ibid., p. 91, pi. xxxvii, figs. 17 — 19. 

— — ^NIerceyi, Coquand. Ibid., p. 93, pi. xxviii, tig. 22; pi. xxix, figs. 

8—14. 

— — Peroni, Co27(nn(/. Ibid., p. 95, i)l. xxxv, figs. 3 — 5 ; pi. xxxviii, figs. 

5—9. 

— — ACANTHONOTA, Coquund. Ibid., p. 103, pi. xxxviii, tigs. 1 — 4. 

1870. — SULCATA, F. Eoiner. Geol. v. Obersehles., p. 343, jjI. xxix, fig. 3. 

— — cucuLus, C. Schliiter. Neues Jalirb. fiir Min., etc., p. 951. 

1871. — SEMIPLANA, F. J. Pictet and G. Campiche. Foss. Terr. CrcH. Ste. 

Croix (Mati'r. Pal. 
Suis.se, ser. 5), p. 321. 

1872. — — H. B. Geinltz. Das Elbtlialgeb. in Sachseu (Palax>nto- 

grafihiea, vol. xx, pt. 2), p. 29, pi. viii, 
tigs. 8-11, 13. 

1873. — FLABELLiFOR.Mis, /. /. iya/(«s'(;rt. Foss. Wliite Cljalk of Simbirsk 

(Iniper. Rusa. Min. Corps 
Instit.), pt. 2, p. 2.10, ]<]. V, 
tig. 3. 

1876. — (Alectryonia) sulcata, D. Braiois. Zeitsclir. f. d. gesanimt. 

Naturwiss., vol. xlvi, p. 
393. 

1877. — se.miplana, A. Fritsch. Suid. im Gebiete der biihni. Kreide- 

foruiat. ii, Weisseuberg. u. Malnitz. 
Schi.ht., p. 141, tig. 138. 

1878. — sulcata, C. Burruig. Ann. Soc. geol. Nord, vol. v, p. 408. 

1882. Alectryonia sulcata, 7/. iSf/i Wider. Zeitschr. d. deutscb. geol. Gesellsch., 

vol. xxxiv, p. 261. 
? 1883. Ostrea semiplana, Frilfch. Op. oit., iii, Iserschioht., p. 121, tig. 97. 

— — FROss, Frlliirh. Ibid., p. 121, fig. 96. 

1885. — akmata, /. Biiloii. Verhaudl. nat. Vereiues preuss. Rlieiul., vol. 

xlii, p. 76. 

50 



382 CRETACEOrS LAM EI.LTIJKAXCHIA. 

1885. Alectktonia crista ungulata, Biihm. Ibid., p. 75, pi. i, fiir. 1. 

1888. OsTREA SEMIPLANA, A. Peron. Hist. Terr, de Ciaie Bassiu Auglo-Parisieu, 

p. 17f>. 

— — Pehoni, Peron. Ibid., p. 180. 

— — SULCATA, G. Miilh'f. Jalirb. d. k. preuss. geol. Landesaust. iiir 

1887, p. 400. 

1889. — SEMIPLANA, E. Hohapfel. Die MoUiisk. Aachen. Kreide (Palieon- 

togiaphica, vol. xxxv), p. 251. j)!. 
xxviii, figs. 5, 6. 

— — GoLDFL'ssi, Holzapft'l. Ibi<l., p. 249, pi. xxviii, figs. 8 — 18. 

— — Bronni, Kohapffl. Iliid., p. 250, pi. xxviii, figs. 3 — 7. 

— — AKMATA, Hohapfel. Ibid., p. 253, pi. xxviii, figs. 1, 2. 

— — Merceyi, Hohapfel. Ibid., p. 251, pi. xxviii, fig. 4. 

? 1889. — SEMIPLANA, Fritsch. Op. cit., iv, Tcplitz. Scliicht., p. 87. 

1889. — (Alectktonia) sulcata, 0. Griepenlcerl. Senon v. Kiiuigslutter 

(Palseout. Abhaudl., vol. iv). 
p. 33. 
1890 — 91. — SEMIPLANA, A. Peron. Deseript. Brachiop., etc., Terr. Cn't.Hauts- 

Plateaux de la Tuui.sie, p. 154. 
? 1893. — — Fritsch. Op. cit., v, Prieseuer Schicbt., p. 102. 

1894. — — B. Ltnidgren. Mollusk. i MammiUatus ocb Mucronata 

zonerna (K. Svensta Vet. - Akad. 
Handl., n.f., vol. xxvi. No. 6), p. 37. 

— — LAEVA, Lundyren. Ibid., p. 37. 

— — SEMIPLANA, A. Henniij. Geol. Foren. i Stockholm Forhandl., vol. 

xvi, p. 514. 

— — cucuLUS, Hennig. Ibid., p. 51(j. 

1895. — Beonni, F. Vogel. Hollandisch. Kreide, p. 7. 

1897. — SEMIPLANA, B. Leonhard. Palaeontographica, vol. xliv, p. 61. 
? — — — Fritsch. Op. cit., vi, Chlomek. Schicht., p. 68. 

— — —A. Biitot. Bull. Soc. Beige Geol. Pal. et HydroL, 

vol. x, p. 25. 

— — (Alectryonia) armata, Biitot. Ibid., p. 23. 

— — SEMIPLANA, ^. ife/ujii/. Eevisioii Lamellibr. i Nilsson's ' Petrific. 

Suecana,' p. 9, pi. i, figs. 7, 10 — 14. Ifl. 
18, 19. 

1898. — (Alectryonia) SEMIPLANA, 0. ilf. Ji'eis. Geoguost. Jahresii. (1897), 

p. 107, pi. iv. fig. 18. 

— — • SEMIPLANA, G. Ml'lhr. Molluskeufaiina Uutersen. v. Braun- 

schweig u. Ilsede, p. 8, pi. i, figs. 1 — 4 ; 
pi. iii, figs. 3, 4. 
19o], — — A. Wall em a till. Jalirb. d. k. preuss. geol. Landesanst., 

vol. xxi (1900), p. 13. 
— — — \iir. AHUXiA, H. Iiid-eller. Paleeoutographic;!, vol. xlviii, 

p. 37, pi. i, figs. 3 — 6. 
y 1902. — ef. SEMIPLANA, A. Wollenianii. Liiueburg. Kreide (Abliandl. d. k. 

preuss. gool. Landesanst., n. k., 
37), p. 49. 



OSTREA. 383 

1002. OsTREA Mkkckyi, WoUemanu. Ibid., p. 51, pi. iii, fis^s. G, 7. 

— — SE5IIPLANA, J. p. J. Eavii. Mollusk. Danniark.s Kiidtafl. i, 

Liiiicllilir., p. llo, pi. iii, figs. 5, 
7, 8. 
1903. Alectryonia semiplana, E. Dacqur. Palaioutographica, vol. xxx, 2, p. 366, 

pi. xxxiv, fii^s. 1 — 4. 
1905. OsTREA se:\iiplana, T. Wegner. Zeitscbi-. d. deutseh. geol. Gesellsch., vol. 

Ivii, p. 177, fig. 10. 

— — armata, Wegner. Hiid., p. 179, figs. 11-^13. 

? 1906. — — L. Kntmhedc. Palseontograpliica, vol. liii, p. 93. 

1908. — Peroni, p. a. Peron. Compte Reudii Assoc. Frauc. Avauc. Sci., 

vol. xxxvi (1907), p. 307. 

1909. — (Alectryonia) Peroni, M. Leriche. Anu. Soe. geol. Nord, vol. 

xxxviii, p. 67, pi. iii, figs. 
20—27. 

— — semiplana, IF. J2o(/«/(ir. Bull. luternat. Acad. Sci. Cracdvie (1909), 

2, p. 690. 
1911. — — Fritsch. Op. cit, Korycaner Schielit., p. 47, fig. 2U. 

1911. Alectryonia semiplana, K. Vogel v. Falcl-ensfeiii. Zeitselir. d. deutscli. 

geol. Gesellsch.. vol. Ixii, p. 559. 

prsrrijitio'i. — Form of sliell extremely variable, depending on the shape, size 
and position of the surface to which the left valve is attached. In many specimens 
tlie shell was fixed to a cylindrical ol)ject {rirli'miiitclla), hut in other cases to a 
flat or .slightly curved surface. 

In the larger, fully grown specimens, in which the attached surface is relatively 
small and mainly in front of the umbones, being either parallel or oblique to the 
hinge, the shell is more or less triangular, or four-sided, or rounded, and its height 
is then often greater than its length (Plate LVII, fig. 7; Text-figs. 183—192). 

When the shell is attached to a cylindrical body the length of which is at right 
angles to the hinge-line, the height of the shell is, at any rate during the attached 
stage, much greater than its length, and the front and back margins are more or 
less nearly parallel (Plate LVII, figs. 8, 12), but subsequently the postero-ventral 
[)art may grow in a posterior direction (Plate LVII, fig. 11). When the length 
of the attached body is parallel or nearly parallel with the hinge-line, and posterior 
to the umbo, the shell becomes much longer than high and extremely ineqnilatei-al 
(Plate LVII, figs. 1 — 3). If the attached surface is directed obliquely backwards 
from the umbo the shell becomes oblique and inequilateral. In small specimens 
having a very small attached surface the shell becomes sickle-shaped and the two 
valves similar in form (Plate LVI, fig. 18). 

During the period in which the left valve is attached to a cylindrical object the 
corresponding i)art of the right valve takes a similarly convex foi-m and remains 
without folds; when the left valve is attached to a flat or slightlv curved surface 



384 



CRETACEOUS LAMELLIBRAXCHIA. 







I 




189 





I :^ 



/ 



191 




Figs. ISi — 102. — Oslvea semiplana, Sowerby. 183 — 190, Zone of BeUmnilMa mwronaia, Norwicb. 
183—185, risybt valvo, and interior and exterior of left valve of one individual; Norwich Museum. 
18(), 18", left ami ri^jlit valves of one individual ; Sedgwick Museum. ISS, left valve (tlie riufbt 
valve is concave) ; Sedgwick Museum. 189, 190, left and riglit valves of one individual ; Norwich 
Museum, No. 2 lul. 191, 192. Zone of Actinocamax gitadi-ahts. East Harnham. Dr. Blackniore's 
Collection. Exterior and interior of a right valve. All x J. 



OSTREA. 385 

the corresponding- part of tlie other valve is nearly flat and smooth (Plate LVIIT, 
figs. 3 — 5j. In the larger specimens with a relatively small attached surface the 
left valve (fig. 188) is more convex than the right, the latter becoming in some 
cases nearly flat or even concave. Tlie free part of the shell develops folds. 
Wlien the attached surface is relatively small the greater part of l)oth valves 
possesses strong radial folds which interlock at the margin of the valves. The 
fohls have more or less rounded summits, sometimes with small ])ointed projections, 
which occasionally develop into spines. The interspaces are usually broader than 
the folds. Well-marked growth-lines run parallel to the folded margin of the 
valves. 

When only the margin of the shell is free no folds are developed, l)ut the edge 
of the shell becomes toothed (Plate LVII, fig. 12) ; when a narrow strip is free 
numerous small folds appear on it (Plate LVII, fig. 13; Plate LVIII, figs. 1 — 
4), forming a corrugated border to the smooth attached part of the shell. 
Occasionally, even Avlien the greater part of the shell i;^ free the folds are indistinct 
(figs. 183 — 185, I'.ll). The direction of growth of the umbo, ai'ea, and ligament- 
pit vary according to the position of the attached surface ; they may be in the 
plane of the valves, or curve inwards or outwards, sometimes becoming nearly 
perpendicular to the plane of the valves of the adult shell. The ligament-pit, area 
and umbones may be at right angles to the length of the shell, or may curve 
obliquely backwards or occasionally forwards. In some cases the area and 
ligament-pit are higher than long, in others longer than high. 

The inner margin of the valves near the umbo often shows crenulations or 
minute irregular ridges. The form of the adductor impression varies with that of 
the shell ; it is vertically elongated when the shell is high, and more rounded when 
the shell is longer. 

AMiiities. — A number of the different forms of this shell have been described 
as distinct species, since many writers have failed to recognise that the mode of 
growth of the shell is determined mainly by the character and position of the 
attached surface. The small sickle-shaped form (Plate LVI, fig. 18), with only a 
small surface of attachment and the two valves similar, was named 0. jmsilla b}' 
Nilsson (1827),! 0. ahvfurmu by Woodward (1833, pi. vi, fig. 1), and 0. Gohlfusxi 
hy Holzapfel (188'J). Small forms which were attached for a longer period to a 
cylindrical object directed more or less nearly perpendicularly to the hinge (Plate 
LVII, figs. 8—11, Plate LVIII, figs. I, 2) and with the margin of the valve folded 
and sometimes extended postero-ventrally were named 0. alsefurmis by Woodward 
(1833, pi. vi, fig. 2), 0. lirouni by Midler (1851),- 0. Peroni by Coquand (18G0). 
A form in which the .shell was attached to a cylindrical object throughout except 

' Hciiiii^' (18'.t7). [.1. i, fi.i,'s. U, -24. 

2 See also Heiiuig (1897). pi. i, fiys. 7, 11. l".'. 



386 



CRETACEOUS la:\iellibkanchia. 



at the actual edge, ■which is toothed (Plate LVII, fig. ]2), Aras named 0. Ncrcei/i 
l)y Coquaiul (]8(50).' Specimens which were attached to a flat object for a long 
period (Phite LVIII, tigs, o — 5) were figured as (h niasformis by Woodward (183:3, 
pi. vi, fig. 3) and 0. aem'rplaitn by Sowerby (1825, the smaller figure). Larger 
forms with a relatively small portion of the anterior part of the shell attached 
to a cylindi'ical object and wnth well-developed folds, were named 0. htxquicostata 
by Woodward (1833, pi. vi, fig. 4), 0. sulcata by Nilsson (1827)," 0. fluheUiformis 
l)y Nilsson (1833),^ and 0. seniiplava by Sowerby (1825, the larger figure) (Plate 
LVII, fig. 7 ; Text-figs. 186, 187, 1 93). The forms like 0. ala'formis and 0. Merceiji 
are common in the upper zones. 0. cnruKita, Sowerby (in Dixon, 1850), is a young 
form of (■*. sfiiiiphuKi. 0. (iniiolu, Goldfuss, is recognised by Coquand and by 
dialler as a form of 0. xriiiijilniKi in which the ril)S have l)ecome spiny. O. 
lirliciiij'oi-iiiis, Co(|uand, is a form in which tlie valves have a rounded outline. 





Fici. I'jy. — Ostrca seniiplana^ Sowoi'by. Zone of Belemnllella nnufonata, Hertford Bridge, Norwich. Dr. Kowe's 
Collection. Exterior and interior of a left valve, x i. 

0. ardiifhoitota, Coquand, is a large form in Avhieli the ribs tend to become spiny. 
(). arculiiKi, Stoliczka, is closely allied to, and may be, as maintained by Peron, 
identical with 0. seniipkoia. 0. BchoiiiJI, Cocpiand (= 0. pJicatiiiouIi-s, Coc\.) and 
0. Jd.uus, Cocjuand, are regarded by Peron as forms of 0. sumiphian. 

The close resemblance between the crenulations on the inner mai-gin of the 
dorsal part of the valves in 0. semijjlana and in 0. rt'siciih(rts, and the occasional 
presence of fine radial ribs on the right valve of 0. seiiiipl((i/ii, suggest tliat these 
two species are rather closely related. 

lli'inarl-s. — The radial folds are usually stronger in examples from the zone of 
Jidimiiiltella mitcroiiata than in those from the lower zones. Occasionally the left 
umbo is exogyriform (Plate LVII, fig. 1 i),but this depends merely on the position 
of the attached surface. 

1 See also Holzapfel (1889) aud Wolloniatm (1902). 

2 Heuuig (1897), pi. i, fig. 18. 

3 Heuuig (1897), pi. i, tig. 16. 



OSTREA. 387 

Ti/pen. — Ostracifes siilcafiift, Blumenbacli, from the Ht-nonian of Salzberg near 
Quedlinbm-g, is stated by Hcnnig to he in the Natural History Museum, Berlin. 
Odrea sp. Mantell, from the zone of Micnistcr ror-KiKjiiiiiinn of Sontherham near 
Lewes, and 0. spmlplann, Sowerby, from the zone of BdomnitelJa mucronnfa of 
Norwich, are in the British Museum. (>. iil,v/(irniis, Woodward, and 0. iiipqjiicdsfiitit, 
Woodwaixl, are from the zone of B. iiiiifniiiiitit of Xoi'wieli ; tlie original of fig. 3 of 
the former is in the Norwich Museum, but the other specimens cannot lie found. 
0. carinain, Sowerby (in Di.Kon), cannot be found. 

DhtribaUon. — Probably zone of TerehratnJina lala of tlie Suutli JJevon coast. 

Zone of HdJaster plnnvs of the South Devon coast, Froxfield (Hants.), White 
Hill near Goring, and Hart's Lock Wood. 

Zone of Micrasfer cor-fi'xfii(Uii(irunii of Stevenage, Strood, and Chatham. 

Zone of Mlcnister cor-aiKjiiinitm of Micheldever, Witherington, Quidhampton, 
Foot's Cray, Southerham (Lewes), Northfleet, New Brompton, Gravesend. and 
Litcham, Norfolk. 

Zone of Marsupites tesiudUutrins of Ovingdean (Susse.K). TJintdcrimix l)and of 
Taplow and the Thanet coast. 

Zone of ActinocamK.v (jiuidrdfrni of East Harnham. 

Zone of Bdi'iiniHeUii viiirnninfn of Ballard Head, Farehnm, Clarendon and 
Norwich. 

Zone of Chlrrri hum fa of Trimingham. 



OsTiiKA s.\RrMKNsi8, sp. ufli: Plate LVIII, figs. G — i». 

Descnption. — Shell thick, higher than long; slightly, modei'ately, or consider- 
able inequilateral. 

Left valve very conve.x, with the attached surface of variable size. Area large, 
high, curved slightly or considerably backwai'ds. Free part of valve with small 
radial folds, and growth-lamella>. Tuner margin Avith a row of small pits. Right 
valve slightly convex, -with a large area ; surface (except of the earlier part) orna- 
mented with numerous small radial ribs sepai-ated by linear furrows, and crossed 
by growth-lamellae. 

4/?i)u/;i«.s.— The high area and the radial folds of the left valve suggest that 
this species may be related to 0. i<emipln)i<i ; it also resembles some forms of 
0. BoHcheroni. Moi"e specimens are needed in order to det(>rmine satisfactorily the 
affinities of this form. 

Tijpe. — \ix Dr. Blackmore's collection. 

Distribution. — Zone of Actiiior.ama.r (jna-'h-ntnsoi Kast llarnliaui, near Salisbury. 



388 CRETACEOUS LAMELLIJiRANCHIA. 



OsTi;i:\ ixcuRVA, mi.i.'^on, 1827. Plate LVIII, figs. 10—13. Plate LIX. 

1827. OsTREA iNCURVA, S. Nilsgoii. Pftiif. Suecaua, p. 30, pi. vii, fit;. 0. 

— — cuRviROSTRis, Nilsson. Ibid., p. 30, pi. vi, tig. 5. 

— — AccTiROSTRis, Nilsson. Ibid., p. 31, pi. vi, fig. G. 

1833. — CURVIROSTRIS, A. Goldfrnn. Petref. Germ., vol. ii, \<. "2-i, pi. Ixxsii, 

fig. 2. 

— — ACUTiROSTis, Guhlfiiita. Iliid., p. 25, ]il. Ixx.xii. fig. 3. 

— — TRIANGULARIS, S. Wood ira rd . Geol. Norfolk, ji. 48, pi. vi. 

figs. 6, 7. 
1837. — ACUTiROSTRis, W. Hisitujer. Letlieea Sueciea, p 47, pi. xiii. 

fig. 6. 

— — CURVIROSTRIS, Hisiiujef. Ibid., p. 48, pi. xiii, fig. 7. 

— — INCURVA, Hislmjer. Ibid., p. 47, pi. xiii, fig. 5. 

1847. — ACUTIROSTRIS, A. d'OrhiijHij. Pill. Franc. Terr. Cret., vol. iii, p. 730, 

pi. cccclxxxi, figs. 1 — 3. 

1849. — TRIANGULARIS, T. Bfown. lUust. Foss. Couil). Gt. Britain and 

Ireland, p. 148, ].l. hi*, figs. 9. 10. 

1850. — CURVIROSTRIS, A. d'Orhujny. Prodr. de Pal., vol. ii, p. 255. 

— — ACUTIROSTRIS, d' OrhUjii ij. Ibid., p. 256. 

— — CURVIROSTRIS, A. Alth. Geogu.-pal. Beschreib. v. Leniborg 

(Haidinger's Naturwiss. Abhaudl., 
vol. iii, pt. 2), p. 254, ])1. xii, 
fig. 38. 

— — ACUTIROSTRIS, Alth. Ibid., p. 254. 

— — — ,0. CURVIROSTRIS, J. Mnrri^. Cat. Brit. Foss., od. 2, 

p. 173. 
1859. — CURVIROSTRIS, J. j1/»7/f;-. Potref. Aacheu.Kreidefoiinat., Supplement, 

p. 7. 

1868. — — E. Eichwahl. Lcthaja Kossiea, vol. li, p. 384. 

1869. — — H. Coquaud. Mon. Ostrea, Terr. Crt't. p.67, pi. xxxv, 

figs. 16—22. 

— — ACUTIROSTRIS, Coqiiniid. Ibid., p. 75, ])1. xxxv, figs. 8 — 15, pi. xxxvi, 

figs. 1 — 5. 

— — TRiNACKiA, Coquand. Ibid., p. 64, pi. XXXV, figs. 23, 24. 

? 1870. — ACUTIROSTRIS, if. OrerfHec. Zeitscbr. d. deiitscli. geol. Gesellsc'li., vol. 

xxii, p. 227. 
1869. — CURVIROSTRIS, £■. i'\icrt'. Moll. Craie de Lemberg., p. 162. 
? 1871. — ACUTIROSTRIS, F. StoUczka. Palseout. ludica. Cret. Fauua S. 

India, vol. iii, p. 471, pi. xlv, 
figs. 1 — 6. 
1878. — CURVIROSTRIS, (?. Behrens. Zeitscbr. deutsch. geol. Gesellscli., vol. 

XXX, p. 260. 
1881. — ACUTIROSTRIS, R. Etiiei'uhjf. Jii Penning and Jukes-Browue, 

Geol. Cambridge, p. 146, pi. iii. 
figs. 5, 6. 



OSTREA. 389 

1881. OsTREA ACUTiROSTKis viir. iNFLEXA, EtJiericlge. Ibid., p. 146, pi. iii, 

figs. 7. 8. 

1888. — coRviROSTRis, .4. Peron. Hist. Terr, de Craie S.E. Bassin Anglo- 

Parisien, p. 173 {partim). 

1889. — — 0. Griepenhet-l. Senou. v. KonigsluUer (Paloeout. 

Abhaudl., vol. iv), p. 34, pi. ii, 
fig.l. 
1891. — — J. BiiJim. Palseoutographica, vol. xxxviii.p. 92, pi. iv, 

fig. 5. 

— — ACUTiROSTRis, Bijhvi. Ibid., p. 92, pi. iv, fig. 11. 

1894. — — B . Ltuuhjren. IsloWnsk. '\ mammillatiis ochmucronata 

zonerua, p. 39. 

— — cuBviROSTRis, LiuidgreH. Ibid., p. 40. 

— — scANiENSis, Lundgren. Ibid., p. 40. 

— — ccRviROSTEis, A. Hfiinlg. Geol. Poreu. i Stoelcholm Furhaudl., 

vol. xvi, p. .514. 

— — ACUTIROSTRIS, HeiDiig. Ibid., p. 514. 

1895. — CORVIROSTRIS, F. Vogel. Holliindiseh. Kreide, ]>. 5. 

— — ACUTIROSTRIS, Vogel. Ibid., p. 5. 

— — SCANIENSIS, Vogel. Ibid., p. 6. 

1897. — iNCURVA, A. Hennig. Revis. Lamellibr. i Nil.'ssou's "Petrif. 

Suecana," p. 11, pi. i, figs. 15, 17, 21 — 
23, 25—28. 

— — ACUTIROSTRIS, F. NotUug. U. Cret. (Maestriclitian) Mari Hills 

(Palseont. Indica, ser. xvi, vol. i), 
p. 37, pi. is, figs. 1, 9. 

1899. — — G. de Alessandri. Palseont. Italica, vol. iv, p. 198. 

1901. — cuRviiiosTRis, n. Tml-eller. Palseoutograpliiia, vol. xlviii, p. 37. 

— — ACUTIROSTRIS, Iitil-eller. Il)id., p. 37. 

? 1902. — — A. Quaas. Palaeontographica, vol. xxx, 2, p. 184, 

pi. xxi, fig. 11. 

— — — E. Bacgw'. Ibid., p. 363. 

— — INCURVA, /.P. /. i2au«. Mollusk. i Danmarks Kridtafl., I, Lamellibr. 

p. 112, pi. iii, fig. 4. 
1906. — — E.Biise. Senon. Cardenas (Bol. Inst. geol. Mexico, No. 24), 

p. 42, pi. i, fig. 5. 

1908. — cuRviBOSTRis, A. Peron. Compte Rendu Assoc. Fran9. Avanc. 

Sciences, vol. xxxvi (1907), p. 306. 

— — — M. Leriche. Ibid., p. 338 (jmrlim). 

1909. — INCURVA, W. Rogala. Bull. Inteniat. Acad. Sci. Cracovie (1909), 

2. p. 691. 

Description. — Shell tliin, usually higher than long ; its form very variable, 
depending on the character and size of tlie attached surface. 

The left valve is flat when attached thi-oughout to a flat surface ; concave Avhen 
attached to a convex surface ; convex when attached to a concave surface or 
when attached to only a small object near the umbo ; irregular when attached to an 

51 



390 CRETACEOUS LAMELLIBRANCHIA. 

irregular surface. When the marginal part is free it grows more or less nearly 
vertical]}- upwards from the attached surface. "When entirely fixed the valve may 
be nearly symmetrical, but has usually a posterior curvature ; when attached l)y a 
small area it usually grows backwards and becomes more or less sickle-shaped. 
The ligament-pit and umbo are straight in the nearly symmetrical forms ; in the 
carved forms they are bent or arched more or less considerably l)ackwar(ls, l)ut 
occasionally forwards. 

The right valve is slightly convex when the entire left valve is attached to a 
flat object ; more convex when it is attached to a convex object ; nearly flat when 
it is attached to a concave object or when attached near the umbo only ; irregular 
and undulating when the attached surface is irregular. The outline of the valve 
and the curvature of the ligament-pit and umbo var^- according to those of the left 
valve. The surface of the right valve sometimes shows concentric ridges, especially 
near the umbo, and when well preserved there are numerous, small, irregular, 
radiating ridges. The inner margin of the valve on each side of the um])o has 
small, transverse, somewhat irregular rounded ridges. The form of the adductor 
impression varies with the shape of the shell. 

Alfinities. — Hennig (1897) has shown clearly that the differences between 
Nilsson's 0. inctirva, 0. ciirnrostris and 0. acutirostris are due to the mode of 
growth, which is determined by the character and size of the attached surface ; and 
for this species Hennig selects the name 0. incnrva. 

0. triangularis. Woodward, which was named 0. trinacria by Coquand, is a 
form in which the entire left vah'e is attached to a flat surface; in the type this 
valve is fixed to a small portion of a large Inoceramvs (Plate LIX, fig. 1-i). 0. 
drejxinon, Wollemann,^ closely resembles the forms like 0. triangularis, and should 
probably be regarded as a synonym of 0. incurva. Gri/pJisea glohosa. Woodward," 
is included in this species by Cocpiand, but in the absence of the type it is difiicult 
to give a definite opinion. D'Orbigny and Peron also include 0. conirosfris, 
Goldfuss. Peron (1888, 1908) regards 0. Wegmanniaita, d'Orbigny, as a form of 
0. incurva. 0. subiincinella, Bohm,^ appears to be closel}' allied to 0. incnrva. 
0. Rahelaisi, Coquand,* from Meudon, resembles closely some forms of 0. incurva 
(Plate LIX, figs. 12 — 14), and should probably be included in that species. 

Some specimens of 0. 'incurva resemble the early parts of 0. semiplana before the 
development of the radial folds. 

Types. — Nilsson's types came from the Upper Chalk of Sweden. 0. triangularis, 

1 ' Liiueherger Kreide' (1902), p. 49, pi. vii, figs. 6, 7. Eogala, 'Bull. Inteniat. Acad. Sci. 
Cracovie ' (1909), 2, p. 691, pi. xxviii, fig. 16. 

2 'Geol. Norfolk ' (1833), p. 52, pi. vi, fig. 8 (from Marham). 

* ' Paleeoutographica,' vol. xxxviii (1891), p. 93, pi. iv, figs. 9, 10. 

* ' Mou. Ostrea, Terr. Crct.' (1869), p. 66, pi. xxxvii, figs. 26, 27. 



OSTREA. 391 

Woodwai'd, from the zone of Ueh-injiilcllK mitrroudtn of Norwich, is in the Norwich 
:\fu.seum (Pkte LIX, fig. U). 

Disfrihutlun. — Chalk Marl (zone of ScMcenbachia varians) of Burham and 
Dover. ^ 

Totteruhoe Stone (zone of Ilolaster snhglohosiis) of Burwell. 

Zone of Bhi/iichoiielhi Cnvlcvl of White Nothe (Dorset), Peter's Pit (Burham) 
and Dover. 

Zone of T('rc'hratii1ina lata of BranseomLe, "Waniford (Hants) and Beachy 
Head. 

Zone of Micraster coy-aiKjaiuitm of Quidhampton, New Brompton, and Grays. 

Zoneoi Marsupitestesfudiiiariiis of Devizes Road (Salisbury), Taplow and West 
Wiekham. Uintacruius band of the Thanet coast. 

Zone of Actinocamax qnadratiis of East and West Harnliani, West Meon, Mottis- 
font, Soberton and Wintei'bourne (Berks). 

Zone of Bdemnitdla mucronata of Alderbury, Clarendon and Norwich. 

Osi'KEA BorcHEROxi; CoquanJ, 1859. Plate LX, figs. 1 — 1-"). 

1859. OsTREA BoucHERONi, H. Coiiuaiid. Bull. Soc. geol. de France, ser. 2, vol. 

xvi, p. 1007. 
1862. — TEVESTHENsis, Coquaml. Gt'ol. Pal. i-eg. sud. Province Constantine, 

p. 227, pi. xix, figs. 7 — 13. 
18C9. — BoucHERONi, Coquaml. Mon. Ostrea, Terr. CrJt., p. 85, pi. xxxi, 

figs. 1 — 3; pi. xxxvii, figs. 1 — 16; pi. 
xxxviii, fig. 20. 
1890-1. — — A.Perou. Deseript. Brach., etc., Terr. Crct. Tunisia, 

p. 142. 
1898. — — G. Midler. Mollusk. Untersen. v. Bi-aviuschweig u. 

llsede (Abhandl. d. k. preuss. geol. 
Laudesaust., n.f., 25), p. 11, pi. iii, 
figs. 5—9. 

Description. — Shell variable in form, usually considerably higher than long, 
with the anterior and posterior margins generally diverging gradually from the 
umbo. Often the .shell is more or less nearly symmetrical, but may be irregular, 
and with the ventral part expanded. 

Left valve very convex, with the anterior and posterior parts sloping rapidly from 
the flank to the margin. The flank is flattened or moderately convex. Umbonal 
region usually narrow and pointed. The attached surface is at the umbo and is 
usually rather small but sometimes large ; when large the height of the shell may 
be relatively small, and the form of the left valve more or less semi-cylindrical. In 

' SjKjciniens of Ostren found in the Upper Greensand of Haldon resrmble eloselv 0. inciirva. 



392 CRETACEOUS LAMELLIBRANCHIA. 

the larger specimens a posterior "wing'-like part is cleveloped, and may be separated 
from the remainder of the valve by a furrow. The surface is marked with 
growth-rings. 

Right valve thin, slightly convex or nearly flat ; umbo small, with the marginal 
part sometimes growing upAvards at a considerable angle with the earlier ]i:irt. 
Surface nearly smooth. 

Affinities. — The English specimens agree closely with the figures given by 
Miiller, and fairly well with some of the smaller examples figured by Coquaud ; 
but the larger forms, in which the height of the shell is relatively less, have not 
been found in this country. 

Specimens in which the attached surface is larger than usual and the height of 
the shell relatively less (Plate LX, figs. 14, 15) resemble some forms of 0. rrslcu- 
laris, and there seems to be almost a complete passage lietween these tAvo 
species; this resemblance has already been noticed by Peron in specimens found 
in the Lower Senonian of Tunis. 

The right valve of small specimens is similar to that of the forms of 0. incarva 
in which the posterior curvature of the umbo is slight. 

The form from Tebessa (Constantine), named 0. tevesthensis by Coquand, Avas 
subsequently identified by that author Avith 0. Boiicherom, and that identification 
has been supported by Peron. 0. liouvilici, Coquand,* from Algeria, resenil)les 
the forms of 0. Bonclicroui which have a short and high shell. 

Remarls. — In England the specimens noAV referred to 0. Boiu-ln'niui liaA'e been 
hitherto identified as 0. Wegmanniana, d'Orbigny,^ l)ut the latter species is 
regarded by Peron^ and l)y Leriche,' as a synonym of 0. iucnrra (p. 088). So 
far as I liaA^e been able to make out the characters of 0. Wcgmanniaiui, from the 
figures of d'Orbigny and Coquand and from the examination of a single right 
A'alve, I am inclined to accept the view of Peron and Leriche. 

This species is often gregarious ; most of the English examples are of rather 
small size, and the left valve is much more frequently fomid than the right vahe. 

Type. — From the LoAver Senonian of Lavalette (Cliarente), said to be in the 
l^cole des Mines, Paris. 

Diatiiliiition. — Zone of Ilohixti'V plama^ of Hitchin. Recorded hy Rowe from 
the Isle of Wight. 

Zone oi Micrader cor-duijitiiiiiin of Whitway (Hants), Farningham Road, Preston 
near Faversham, Gravesend, Charlton, and Loam Pit Hill (Lewisham). 

> 'Geol. Pal. reg. sml. Province Coustantine ' (1862), p. 232, pi. xxii, figs. 9—10; aud 'Mem. 
Ostrea, Terr. Crct.' (1809), p. 89, pi. xxi, figs. 3—6, pi. xxiv, figs. 7—11. 

2 'Pal. Franc. Terr. Crt't.,' vol. iii (1847), p. 749, pi. cccclxxxviii, figs. 6—8. Coquand, op. cit. 
(1869), p. 53, pi. iv, figs. 9 -11,'pl. xxiii, figs. 11 — 14. Alessandri, ' Pal. Italica,' vol. iv (1899), p. 198. 

•' ' Hist. Terr. Craie, S.E. Bassiu Anglo-Parisien ' (1888), p. 173. 

■' 'Compte Kendu Assoc. Fran?. Av. Sci.,' 1907, pt. 2 (1908), p. 338. 



OSTREA. 393 

Zone of MavioipileK tc.'^fitdiiiariiiK of Farnborougb, Ropley, Taplow, and Brighton. 
Recorded by Rowe from tlic Sussex and Tlianet coasts. 

Utntacrinvs band of Devizes Road (Salisbury) ; Odehani, Alresford, and Itclien 
Abbas (Hants) ; Margate. 

Zone of Aft'uiocamax iiitadnifiix of Bullington, Ropley, Wield, Andover, and 
Rottingdean. 



OsTEEA LUNATA, XllsxoN, 1827. Plate LX, figs. IG— 1<>. Plate LXI, figs. 1—0. 

1816. OsTEEA CANALicuLATA, /. Sotferlij. Miu. Concli., vol. ii, p. 81, pi. cxxxv, 

fi^'. 1. (Nou canalicvlata, Soweibv, 
1813). 

1827. — LUNATA, »S'. Nilsson. Pfti-if. Suecaua, p. 31, pi. vi, fig. 3. 

1833. — —A. Goldfuss. Petref. Genu., vol. ii, p. 11, pi. Ixxv, Cg. 2. 

1834. — nxsvTA, S. G. Morton. Svnop. Org. Remains Cret. XJ. States, p. 51, 

pi. ix, fig. 6. 
? — — MESENTERicA, Mortoii. Ibid., p. 51, pi. ix, tig. 7. 

1837. — LUNATA, W. Hisinger. Lethsea Suecica, p. 49, pi. xiv, fig. 4. 

1849. — — T. Brown. lUustr. Foss. Conch. Gt. Britain aiul hvlautl. 

p. 147, pi. Ixi*, figs. 20, 21. 
1854. — LARVA, J. Morris. Cat. Brit. Foss., ed. 2, p. 173. 
1869. — UNGULATA, H. Coquatul. Men. Ostrea, Terr. Crt't., p. 58 (jMrtim), 

pi. xxxi, figs. 6—8 (? 9, 10). 
r" 1870. — LUNATA, H. Crediier. Zeitschr. d. deutsch. geol. Gesellsch , vol. 

xxii, p. 227. 

1884. — (Alectryonia) LARVA, C. ^. TI7/(7i'. Ostreida; of N.America (4tli 

Aun. Rep. U.S. Geol. 
Survey), p. 296, pi. xlii, 
figs. 2—5. ? 6 (not 7—9). 

1885. — LARVA var. NASUTA, it*. P. H7/;7M(?. Brach. and Lamellibr. Raritan 

Clays (Mou. U.S. Geol. 
Surv., vol. ix), p. 34, pi. iii, 
figs. 3, 4. 

1894. — LUNATA, A. Henniij. Geol. Foreu. i Stockholm Furhaudl., vol. xvi, 

p. 515. 

1895. — (Alectrtonia) lunata, F. Vogel Holliindisch. Kreide, p. lO. 
1897. — LUNATA, A. Hennig. Revis. Lamellibr. i Nilsson's "Petrific. 

Suecaua," p. 14. 
1907. — NASUTA, S. Weller. Cret. Pal. New Jersey, p. 447, pi. xliii, figs. 7, 8. 
? — • — MESENTERICA, Weller. Il)id., p. 446, pi. xliii, figs. 9 — 14. 

Description. — Shell inequivalve, elongated between the umbo and the posterior 
extremity, curved regularly, usually sickle-shaped. 

Left valve moderately or slightly convex, the part near tlie umbo being more 
convex than the later part. Finl)o small, usually curved posteriorly, with, in nearly 



394 CRETACEOUS LAMELLl HRANCHIA. 

all cases, a very minute surface of attaclnnent ; on cacli side of tlie umbo is a 
wing-like or ear-like extension. The early part of the shell is smooth except for 
concentric lines or ridges and occasionally fine radial furrows ; in the adult the 
anterior and ventral marginal parts develop broad rounded folds. The stage at 
which the folding begins and the size and iniml)er of the folds, vary in different 
individuals. Small folds sometimes occur on the jjosterior wing-like part. The 
ligament-pit is sometimes straight Ixit usually curves posteriorly. 

Eight A'alve at first smooth and nearly flat, occasionally slightly concave, but 
afterwards becoming folded like the left valve. Umbo very small. 

Affinities. — Most writers, following the example of Coquand, have united 
(). hiiKitit, Xilsson, with 0. niiguiafd (Schlotheim),' regai'ding the former as a 
young stage of the latter. Hennig (1894, 1897) and Vogel (1895), however, do not 

'■ Kuorr, ' Recueil. Monum. Castast, Pctrificat.,' toI. ii (17G8), p. 130, P. II, pi. Dvii, figs. 5, 6. 
Bruguiere, 'Hist. nat. Vers et Mollusques (Eucyol. iiu'thod.), Planches,' vol. iv (1827), pi. clxxxviii, 
tigs. 4, 5. Faujas-St.-Fond, ' Hist. uat. Mte. Ste. Pierre ' (1"99), p. 150, pi. xxiii, fig. 6. Ostracites 
umjulatus, v. ScLlotheim, iu Leouliard's ' Tascheub. fiir Min.,' vol. vii, pt. 1 (1813), p. 112 ; 0. crista 
iiieleagris, ScLlothem, ibid., p. 112. 0. larrn, Lamarck, ' Auiniaux sans Vert.,' vol. vi (1819), p. 216 ; 
O. dorii/eUa, Lamarck, ibid., p. 210. ? 0. falcafa, Morton, 'Amer. Journ. Sci.,' vol. xvii (183U), 
p. 284; vol. xviii (1830), pi. iii, figs. 19, 20. 0. larva, Goldfuss, ' Petref. Germ.,' vol. ii (1833), p. 10. 
pi. Ixxv, tig. 1. V 0. falcafa, Morton, ' Syuop. Org. Eem. Cret. U. States' (1834), p. 50, pi. iii, fig. 5 
Ah'HnjuHia acroclonte, Fischer de Waldheim, 'Bull. Soe. Imp. Nat. Moseou,' vol. viii (1834 — 5), 
p. llfJ, pi. V, tig. 2. 0. larva, d'Orbiguy, ' Pal. Frau9. Terr. Crct.,' vol. iii (1847), p. 740, pi. cecclxxxvi, 
figs. 4, 5, 8 (? 6, 7). 0. larva, Miiller, ' Petref. der Aachen. Kreidef ,' pt. 1 (1847), p. 39. 0. tegulanea, 
Forbes, ' Trans. Geol. Soc.,' ser. 2, vol. vii (1846), p. 1.56, pi. xviii, fig. 6. 0. ponticeriana, d'Oi-yn^ny, 
' Voy. Pol. Slid et TOccanie. Atlas Gt'ol.' (1847), pi. viii, figs. 45, 46. ? 0. larva ?, Kner, ' Kreidenieig. 
v. Leuiberg' (1850), p. 30, pi. v, fig. 4. 0. « ro(;a //;', Queustedt, 'Handb. d. Petrefactenkunde' (1852), 
p. 499, pi. xl, fig. 24. 0. larva, Beyrich, ' Zeitscbr. deutsch. geol. Gesellsch.,' vol. iv (1852), p. 153, 
pi. iv, fig. 3. ? O.frons, Kner, ' Denkschr. Akad. Wiss. Wieu, Math.-uat. CI.,' vol. iii (1852), p. 319, 
pi. xvii, fig. 10. ? 0. larva, F&vve, ' Moll. Foss. de la Craie de Lemberg' (1869), p. 160. O. mujKlata, 
Coquand, ' Mon. Ostrea, Terr. Crct.' (1869), p. 58 (jwW/jh), pi. xxxi, figs. 4, 5, 12—15. 0. {Alec- 
injonla) iinijiilata, Stoliczka, ' Cret. Fauna S. India,' vol. iii tlS71), p. 470, pi. xlvii, figs. 3, 4. 0. larva, 
Lartet, 'Ann. Sci. geol.,' vol. iii (1873), ]>. 59. Alectryoitia larva, Schroder, 'Zeitscbr. d. deutsih. 
geol. Gesellsch.,' vol. xxxiv (1882), p. 262. 0. (Alectryonia) larva. White, ' Ostreidse of N. America' 
(1884), p. 296, pi. xlii, figs. 7—9. 0. inujulata, Peron, ' Hist. Terr, de Craie S.E. Bassiu Anglo- 
Parisien' (1888), p. 178. 0. (Alectryonia) larva, Griepenkerl, ' Seuon. v. Kouigslutter ' ('Palajout. 
Abluuull.,' vol. iv, 1889), p. 33. 0. nngulata, Holzapfel, ' MoUusk. Aachen. Kreide ' (' Palaeonto- 
graphica,' vol. xxxv, 18S9), p. 250. Alectryonia ungulata, Newton, ' Quart. Journ. Geol. Soc.,' vol. 
xlv (1889), p. 333, pi. xiv, fig. 12. 0. nngulata, Peron, 'Descript. Brach., etc., Terr. Crct. Tunisie ' 
(1890—91), p. 185. 0. ungulata, BiJhm, ' Palieontographica,' vol. xxxviii (1891), p. 91. A. ungulata, 
Newton, ' Joui-n. Conch.,' vol. viii (1896), p. 136. 0. (Alectryonia) ungulata, Notliug, ' U. Cret. 
(Majstrichtian) Mari Hills ' (' Palaont. Indica," ser. xvi, vol. i, 1897), p. 38, pi ix, figs. 4, 5. ? 0. cf. 
larva, Quaas, ' Palajontographica,' vol. xxx, 2 (1902), p. 187, pi. xxi, fig. 12. 0. (Alectryonia) ungttlata, 
Boule and Thevenin, 'Annal. Palt'ont.,' vol. i (1906), p. 48 [6], pi. i, fig. 5. A. larva, Krunibeck, 
' Palseontographica,' vol. liii (1906), p. 96, pi. vii, fig. 10. 0. (Alectryonia) ungulata, Pcthii, ibid., 
vol. Hi (1906), p. 185, pi. xii, fig. 1. 



EXOGYRA. 395 

accept this view, and consider that 0. lunata is a distinct species. The\- have 
studied a large series of specimens agreeing with Nilsson's type, and do not find 
any transitions between 0. linmtd and 0. nngnlatn. After examining a large 
number of specimens of 0. hniafa from Trimingham and comparing them with 
foreign examples and figures of 0. niujnldta, I am led to accept the conclusions of 
Hennig and Vogel. From the character of the margin of the shell these specimens 
appear to be fully grown individuals and they are not associated with any 
examples agreeing with Schlotheim's species. In 0. uuijnlaUt the early part of 
the shell resembles the adult of 0. lunnta, but subsequently it becomes more 
elongate and develops much deeper folds on the posterior as well as on the anterior 
margin, consequently the valves become nuich deeper and more nearly equal than 
in 0. lunata. Since the folding starts at a later stage in 0. lunata than in 0. inir/u- 
Jata, it is difficult to see how individuals of the former could ever develop into the 
latter as has been supposed by some writers. 

Some of the small, sickle-shaped forms of 0. xrvdpUinii show some resemblance 
to 0. hnutfd, but their attached surface is usually larger and their folds are smaller 
and more numerous and occur on the posterior as well as the anterior margin. 

Bemarls. — 'Mv. Brydone has found a few examples of 0. Initafa in which the 
left valve is entirely attached to the surface of echinoids. 

Ti/pes. — 0. cannliciilata , Sowerby, from Trimingham, is in the British Museum. 
0. Itmntd, Nilsson, is from the Ahus-sandstone. Hennig states that the figure 
given by Nilsson does not correctly represent the folds. 

Distribution. — Upper Chalk (zone of Ostrea lunatii) of Trimingham, Norfolk. 



Geims—'ExoGYJi.K, T. Saij, 1820. 

(' Amer. Journ. Sei.,' vol. ii, p. 43). 



ExoGYBA siNUATA {Soivevby), 1822. Plate LXI, fig. 13. Text-figs. 194—214. 

1821. Gryph^ea Couloni, M. J. L. DeJ'raiice. Diet. Sei. nat., vol. xix, p. 63-1. 

— — DuMEBiLii, Defrance. Ibid., p. 535. 

1822. — si.N-CATA, /. Sowerbij. Min. Couch., vol. iv, p. 43, pl.'eccxxxvi 

(nou Ostrea slnuata, Lamarck, 1819). 

_ AQDILA, A. Bronguiart. In Cuvier's Ossem. Foss., vol. ii, pp. 

332, 614, pi. ix, fig. 11. 
1829. — SINUATA, J. riiiUips. Giol. Yorks., p. 122, pi. ii, fig. 23. 

— ExoGTRA L.«viGATA, Snifcrbij. Mill. Coiicb., vol. vi, p. 220, pi. Jcv, fig. 4. 
1833. — A<iUii.A, A. Gohl/itss. Pelref. Gciui.. vol. ii, p. 36, pi. Ixxxvii, 

fig. 3. 



^96 CRETACEOUS LAMELLIBRANCHIA. 

1836. OsTREA FALciFORMis, f. A.Komer. Die Versteia. uord-deulsch. Ool.-Geb., 

p. 59. 

1837. Amphidonte aquila, G. G. Pusch. Polens Palaout., p. 38. 

18-10. ExOGYRA siNUATA, A. Leymefie. Bull. Soc. gc'ol. de France, vol. xi, p. 121 

(vars. suhsinuata, etc., p. 124). 

1841. — — F. A. Riimer. Die Verstein.d. nord-deutsch. Kreidegeb., 

p. 47. 
? — — vn DATA, Riimer. Ibid., p. 47. 

1842. — siNUATA et suBsiNUATA A. Leymevie. Mem. Soc. geol. de France, 

vol. V, pp. 16, 17, 28, 
pi. xii. 

1845. Gryph.ea SINUATA vars. ljsvigata, subsinuata, Couloni, E. Forbes. 

Quart. Journ. Geol. Soc, vol. i, p. 250. 

1846. EsooYRX siavxTX, A. Leymerie. Statist, gcol. et miu. de I'Aube, pi. vi, 

fiR.l. 

— — subsinuata, Lcymerie. Ibid., pl. vii, ti;^. 3. 

— — — var. Aq,\jii,lVA, Leymerie. Ibid., pl. vii, fig. 4. 

1847. OsTREA Couloni, A. d'Orhigny. Pal. Fran?. Terr. Cit't., vol. iii, p. 698, 

pl. cceclxvi, figs. 1 — 4; pl. cccclxvii, 
figs. 1—3. 

— — AQUILA, A. (VOrljujny. Ibid., p. 706, pl. ceoclxx, figs. 1 — 4. 

? — EsoGYRA SINUATA, A. (VArcliiac. Mem. Soc. gcol. de France, ser. 2, vol. ii, 

p. 313. 
1849. GRYPH.a;A sinuata, T. Brown. Illustr. Foss. Conch. Gt. Brit, and Ireland, 

p. 149, pl. Ix, fig. 5. 

— — aquila. Brown. Ibid., p. 150, pl. Ixi*, figs. 17 — 19. 

— — i..'EViQATA, Brown. Ibid., p. 149, pl. Ix, fig. 17. 

1860. ExooYRA aquila, /. Ewald. Zeitschr. d. deutsch. geol. Gesellsch., vol. ii, 

p. 470. 
1853. Ostrka aquila, F. J. Pictet and W. Ronx. Moll. Foss. Gres verts de 

Geneve, p. 520, pl. xlviii, 
figs. 1, 2. 
1864. ExoGYRA SINUATA, J. Morris. Cat. Brit. Foss., ed. 2, ]). 167. 
1855. OsTREA Couloni, G. Coiteau. Moll. Foss. de I'Youue, p. 122. 

— — AQUILA, Cotteau, Ibid., p. 122. 

1858. — Couloni, F. J. Pictet and E. Renevier. Foss. Terr. Aptien (Mater. 

Pal. Suisse, ser. 1), p. 
138. 

1859. — — /. Vilanova-y-Piera. Mem. geog.-agric. de Castellon, pl. 

iii, fig. 24. 

1861. — — P. de Loriol. Auim. Invert. Foss. Mi. Saleve, p. 110. 

1868. — — de Loriol. Valangin. d'Arzier (Vaud). (Mater. Pal. 

Suisse, ser. 4), p. 51. 

— ExoGYKA aquila, E. EichwaUl. Lethaea Eossica, vol. ii, p. 399. 

1869. Ostrea Couloni, P. de Loriol and V. Gillieron. TJrgon. infer. deLauderon, 

p. 24. 

— — aquila, H. Coqnand. Mon. Ostren, Terr. Cret., p. 158, pl. Ixi, figs. 

4—9. 



. EXOfJYKA. ■ 397 

18(59. OsTRBA CouLONi, Coquand. Ibid., p. 180, pi. Ixv, fig. 10 ; pi. l.xxi, figs. 8—10 ; 

pi. Ixxiv, figs. 1—5; pi. Ixxv, figs. 1—6, 22. 
18/0. — — L. Dieidafait. Bull. Soc. geol. France, ser. 2, vol. xxvii, 

p. 431. 
^^^^- — ^- J- Piclet ami G. Campichc. Foss. Terr. Crct. Sto. 

Croix (Mater. Pal. 
Suisse, ser. 5), p. 287, 
pls.clxxxvii.clxxxviii, 
cxcii, fig. 1. 
1875. ExoGTRA siNUATA, /. PhUUps. Gool. Yorks., Part i, ed. 3, p. 244, pi. li, 

fig. 23. 

— — SUBSINITATA, PhilUps. Ibid., p. 244. 

1877. OsTREA CouLONi, G. Bohm. Zeitschr. d. deutsch. geol. Gesellsch., vol. xxii, 

p. 231. 

1878. ^TosTREON LATissiMUM, E. Bcujle. Explic. Carte geol. France, vol. iv, 

pt. 2, Atlas, pi. cxxxix, figs. 1—3. 

— — coNSOBEiNus, Bayle. Ibid., pi. cxxxix, fig. 4. 

— — CouLOKi, Bajjle. Ibid., pi. cxl, figs. 1, 2. 

— — AQUiLiNUM, Bayle. Ibid., pi. cxl, figs. 3—5. 

? 1883. OsTREA (ExoGYEA) CouLONi, W. Keeping. Foss., etc., Neoc. Upware and 

Brickhill, p. 100. 
1884. — — 0. Weerth. Fauna d. Neoconi. im Teuto- 

burg. Walde (Palaeont. 
Abhandl., vol. ii), p. 55. 
1884. ExOGYRA AQuiLA, C. A. White. Foss. Ostreidas of N. America (4tli Ann. 

Rep. U.S. Geol. Sui-v.), p. 304, pi. liii, 
fig.s. 1, 2. 
1886. — CouLONi, //. Tmidschohl. Nouv. Mem. Soc. Imp. Nat. Moscou, 

vol. XV, p. 133. 
1889. — SINUATA, G. W. Lamphigh. Quart. Jouru. Geol. Soc, vol. xlv, 

p. 615. 
1891. — CouLONi, 0. Behreiulseii. Zeitschr. d. deutsch. geol. Gesellsch., 

vol. xliii, p. 419. 

1895. OsTREA (Exogtra) Couloni, G. Maas. Ibid., vol. xlvii, p. 270. 

1896. Exogtra Couloni, A. WoIIemann. Ibid., vol. xlviii, p. 831. 

1897. — SINUATA, B. B. Newton. Proc. Dorset Nat. Hist, and Antiq. 

Field Club, vol. xviii, ]>. 74,' pi. ii, 
figs. 2, 3. 
? 1897. — A<juiLA, K. Gerhardt. Neues Jahrb. fiir Min., etc., Beil.-Bd. xi, 

p. 175, pi. iv, fig. 10. 
1000. — Couloni, A. WoUemann. Die Biv. u. Gastrop. d. deutsch. u. 

holli'ind. Neocoms (Abhandl. d. k. 
preus.geol. Landesanst.N.F.,pt.31), 
p. 8, pi. i, fig. 1. 
? 1903. — f/. Couloni, W. Paiilike. Neues Jahrb. fiir Min., etc., Beil.-Bd. 

xvii, p. 291. 
.'1904. — CovLo^i. E. Dacque. Beit r. Paliiont. u. Geol. Osterr.-Ungai-ns u. 

d. Orients, vol. xvii, p. 14, pi. ii, figs. 6 — 8. 

52 



398 



CRETACEOUS LAMELLIBRAXCHIA. 



1905. ExOGYEA CouLOSi, E. Ilarhorl. Fauna d. Scliaumburg - Lippf'scheu 

Kveidemulde (Abhaudl. d. k. 
preuss. geol. Landesanst., n.f., 
45), p. 30. 

1907. — — 0. Hanpt. Neues Jahrb. fiir Min., etc., Beil.-Bd. 

x.xiii, p. 211. 

1908. — — A. A. Sfojanoff. Auii. gcol. et min. Russie, vol. x, 

p. 119. 



.' r. 




\^ 







Fig. 194. — Exogyra simtafa (Sow.) Ilytlic Beds, Sevenoaks. Sedgwick Museum, Cambridge. Left 

valve. X 3. 

Bescri])tion. — Shell ^\\t\\ subtrigonal, snbquadrate, oval or rounded outline ; 
often large and massive. The posterior margin is truncated ; in the early stages of 
growth it is either nearly straight or slightly concave ; later it becomes more 
concave, with an angular projection at its dorsal and at its ventral end ; in large 
specimens this margin usually becomes more rounded. The anterior and ventral 
margins usually form a convex curve. In large specimens the postero-dorsal 
margin is sometimes nearly straight. In many small, and in some large specimens, 
the height of the shell is distinctly greater than the length, l)ut in others, particu- 
larly large forms, the height and length are nearly equal. In some of the high 
forms the shell is considerably arched, the posterior part being concave. 

Left valve moderately or very convex. Umbo often relatively small, usually 
spiral, with a moderate or large backward curvature. The surface of attachment is 



EXOGYRA. 



399 




197 



Figs. 195— 108.— Ejoji/.a sitinuta (Sow.). Left valves, lil"), I'.lT, 198, Sodipvick Museiiin. 19C. Mr. 
Lampluijh's CoUettiuii. 195, Hytlie Beds, Hythe. UlU, Speeton Clay (zoneof Bt(i'i"iM(<s?a(ti<i;is), 
Speeton. 197, Tealliy Limestone, Claxby. 198. Ferruginous Sands, Atherfield. All x J- 



400 



CRETACEOUS LAMETJJBRANCHIA. 




202 



203 



Figs im— 203.— Exorjyra sinuata (Sow.). Sodtjwiclc Musuuui. 199, 200, right aiiJ left valves of one 
specimen ; Lower Greensand, Atliertielil. " 201—203, left valves. 201, 202, Tealby Limestone, 
Claxby. 203, Claxby Ironstone, Donnington. All x J. 



EXOGYRA. 401 

behind the uml)o and is usually of small or moderate size. A carina extends in a 
curve from the umbo towards the postero-ventral extremity, and sometimes bears 
coarse tubercles or spiny projections ; it is at first strong, and may be continued to 
the postero-ventral margin of the valve, which is then angular; but in large 
specimens it often becomes indistinct during the later stages of growth and may 
ultimately disappear. Usually the carina is angular at first and becomes rounded 
later, but it may be angular throughout or rounded throughout; sometimes it 
divides the valve into two nearly equal parts, but usually the anterior is larger 
than the posterior part. The former is convex ; the latter is flattened or concave 
or undulating, and its slope to the posterior margin is often gradual, but may be 
steep or even perpendicular. The surface of the valve bears distinct growth- 
lines, and sometimes shows faint radial folds. The curvature of the ligament-pit 
varies with that of the umbo. 

Right valve usually nearly flat or slightly concave or undulating, but sometimes 
very concave. Its outline varies as in the left valve. Umbo small, more or less 
considerably spiral. Surface with growth-lines and occasionally with faint radial 
ribs. Adductor impression large, oval, usually sub-median. 

Affinities. — By some authors, especially Leymerie and Coquand, the forms 
similar to the types of Gnjplma siiiuata, Sowerby, and G. aqiiila, Brongniart,' 
have been regarded as specifically distinct from those like Exogi/ra subsinuato, 
Leymerie-; but Pictet and Renevier (1858), after studying a large series of 
specimens from Switzerland, France, and England, came to the conclusion that it 
was impossible to separate these as two species ; the same view was maintained by 
Pictet and Campiche in 1871, and has been supported more recently by WoUemann 
(1900), who has examined a large series of specimens from North Germany. 
Pictet, Renevier and Campiche showed that the two forms are not, as Leymerie 
maintained, characteristic of different horizons, but occur together, although varying 
in abundance at different levels. The study of numerous English and some foreign 
specimens leads me to endorse the view first expressed by Pictet and Renevier. 
The variation is found to be extremely great, and the different forms are connected 
by numerous gradations. It is also noticeable, as Pictet and Renevier pointed out, 
that the varieties of suLsinuata, some of which were named aquiliiin, dorsafa, 
and falcifem by Leymerie, may differ from one another more than they do from 
simoatii. The forms of the siiuinta (aquila) type are common in the Atherfield 
and Hythe Beds, and those of the snhsimiata type occur mainly in the zones of 
Bdemnites lateralis and B. jarnlnm, but neither is confined to those horizons. 

' See figs. 194, 195, 199, and the figures of Sowerby (1822), Brougniart (1822), Pictet aud Roui 
(1853), Leymerie (1846), pi. vi, fig. 1. 

2 See figs. 202, 203, 206, 212, 214, and Leymerie (1842), pi. xii, figs. 3, 7 ; (1846), pi. vii, 
figs. 3, 4. 



402 



CRETACEOUS LAMELLIBRANCHIA. 




Figs. 20i-2ia.-Exo,jyra sinuata (Sow). 204, 205, left an,l li-ht valves of one uulividual ; Hythe 
lieds, Ilythe; Seds,nvick Museum. 206, 207, 210, Claxby Ironstone, Uonmn^'ton ; bedgwick 
Museum ; 20(5, 210, left valves ; 207, right valve of 20(5. 208, 209, Hythe Beds Hythe. Museum 
of Practical Geology, No. 21W21. Left and right valves (/,rri(7«(a form). 211 bpeeton C aj, 
(zone of B. JateralU). Speeton. Mr. Lan.plugh's Colleetion. Left valve. 2 2, 2Ki. Speeton Clay, 
Speeton. Sedgwick Museum. Left and right valves ot one individual. AU x „. 



EXOGYRA. 



403 



Exogi/ra imbricata, Krauss/ from the Uitenhage Series, is closelj^ allied to E. 
Couloni. 

Remarls. — The proportion of the height to the length of the shell varies con- 
siderably. In some specimens the height is much greater than the length, but in 
others the two diameters are nearly equal. In the latter case the left valve is usually 
less convex relatively than in the higher and more strongly carinate forms. In the 
specimens in which the carina reaches the margin the postero- ventral extremity is 
more angular than in those in which it becomes indistinct. The slope of the pos- 
terior part of the left valve is gentle in the forms in which the height and length are 
nearly equal, but becomes steeper in the higher and more strongly carinate forms. 




Fig. -Zl-i.—Exogyra sinuata (Sow). Speeton Clay (probably zone of Belemnites lateralis), Speeton. 
Sedgwick Museum. Left and right valves, x J. 

and is sometimes, as in the example figured by Phillips (1822), perpendicular to 
the plane of the valves (fig. 211). In that type, which is an extreme example, the 
umbo is only slightly curved, but this form passes gradually into others with a 
strongly curved umbo. Indications of radial folds are seen in some specimens, 
but they are less distinct than in some foreign examples. 

Some specimens show that the stage in which the posterior margin is sinuous 
is preceded by one in which it is only slightly concave (fig. 199). The type of 
Gnjphsea aquila, Brongniart, is a small example of the shmafa form with the carina 
continued to the margin. The specimen figin-ed by Pictet and Roux is similar, but 
larger, and with the carina becoming indistinct towards the margin ; the large 

1 ' Nova Acta Acad. Cses. Leop.-Carol. Nat. Cur.,' vol. xsii (1850), 2, p. 460, pi. 1, fig. 2. Sharpe. 
'Trans. Geol. Soc' ser. 2, vol. vii (1856), p. 197, pi. xxiii, fig. 3. Kitcliin, 'Ann. S. African Mus," 
vol. vii (1908), p. 77. 



404 CRETACEOUS LAMELLIBRANCHIA. 

rounded forms (like Sowerby's siiutata) are older individuals of the same tj'pe, and 
sometimes attain a height of 8 or 9 inches. 

A small, oval, very inequilateral form, with a rounded carina, was named Ed-ogyra 
leengata by Sowerby (1829), and -was stated to have come from the Irish Green- 
sand. An examination of the type shows clearly that it was not obtained from 
that deposit, but from the Hythe Beds ; the form of the shell and the character of 
the matrix agree perfectly with other examples which have been found in the 
Hythe Beds (figs. 208, 209). 

The examples from the Lower Greensand of Upware, which were referred Ijy 
W. Keeping to Exogyra Gouloni, probably belong to this species, but the specimens 
seem to me too few and not sufficiently perfect to enable the identification to be 
made with certainty. 

In England Sowerby's name {sinuata) has been generally used for this species, 
but Defrance's name {Gouloni) has been adopted by foreign writers; the former is 
used here since, although Defrance's name has priority, the description was 
scarcely sufficient for identification and was not accompanied by either a figure 
or a reference to a figure. 

Types. — Gryphsea Gouloni, Defrance, from the neighbourhood of Neuchatel. 
G. dnuata, Sowerby, from the Hythe Beds of Ashford, and E. laevigata from the 
Hythe Beds, in the British Museum. G. aquiln, Bi'ongniart, from the Upper Aptian 
of the Perte du Rhone. G. sinuata, Phillips, from the Speeton Clay, in the York 
Museum. Exogyra suhsinuata, Leymerie, from the Neocomian of the Aube. 

Distribution. — Atherfield Beds of Atherfield, Compton Bay and Sevenoaks. 
Ferruginous Sands of Atherfield and Shanklin. Hythe Beds of Hythe, Lynipne 
and Maidstone. Folkestone Beds of Folkestone. Mammillatas bed of Okeford 
Fitzpaine (Dorset). Speeton Clay (zones of Belemnites lateralis, B. jaculmn and B. 
b runs vice nsis) of Speeton. Claxby Ironstone (zone of B. lateralis) of Donnington. 
Tealby Limestone (zone of B. brunsvicensis) of Claxby. 



Exogyra tuberculifeka, Koch and Dnnl-er, 1837. Plate LXI, figs. 7 — 11. 

1835. Exogyra aviUAi^ia, F. A. liiJmer. Versteiu. uord-deutsoli. Oolith.-geb. p. 65 

{partim), (non E. sinralis, Goldfuss). 
1837. — TUBERCULIFEKA, F. C. L. Kock uiid W. Bunker. Nord-deutsch 

Oolith.-geb., p. 64, pi. vi, fig. 8. 
? 1839. — suiiPi.icATA, F. A. liiiiiicr. Versteiu. uord-deutsch. Oolith.-geb., 

Nuchtrag., p. 25, pi. xviii, fig. 17. 

1841. — — Mumer. Die Verstein. d. nord-deutsch. Kreidegeb., 

p. 47. 

TUBERCULIFEBA, lithiivr. Ibid., p. 48. 

1842. — SUDPLICATA, A. Leymerie. Mt'ni. Soc. geol. de Frauce, scr. 2, 

viil. V, p. 18, pi. xi. figs. 4 — 6. 



EXOGYRA. 405 

1845. GrRTPHiEA HABPA vars. SUBl'LICATA ft SEMIPLICATA, E. Fufbes. Quai't. 

Journ. Geol. Soc, vol. i, p. '250, pi. iii, fig. 12. 
1847. OsTREA BoussiNGAULTi, A. (VOfbhjny. Pal. Fraii9. Terr. Crct., vol. iii, 

p. 702, pi. cccclxviii, figs. 6—9 
(non figs. 1 — 3 = 0. Minos, 
Coquand). 

1853. — HARPA, F. J. Pictef and W. Roux. Moll. Foss. Grt-s verts de Geneve, 

p. 526, pi. xlix, fig. 2. 

1854. ExoGYRA HARPA, /. Moiris. Cat. Brit. Foss., ed. 2, p. 166. 

1855. OsTREA BoussiNGAULTii, G. Cotteau. Moll. Foss. de TYoiiue, p. 121. 
1858. — BoussiNaAULTi, F. J. Pictet and E. Benevir. Foss. Teir. Aptieii 

(Mater. Pal. Suisse, ser. 1), p. 140, pi. xix, 
fig. 5. 

1868. — — P. de Loriol. Valaugien d'Arzier (Mater. Pal. 

Suisse, ser. 4), p. 50, pi. iii, 
figs. 14—16. 

1869. — — P. de Loriol and V. Giltii'ron. Urgou. infer. Lan- 

deron, p. 26, pi. i, fig. 23, 
pi. ii, figs. 1 — 4. 

— — — H. Coquand. Mon. Ostrea, Terr. Crct., p. 161 

{partim), pi. Ixiv, figs. 8 — 13. 

— — TDBERCULiFEKA, Cojwaftrf. Ibid., p. 189, pl. Ixiii, figs. 8, 9 ; pi. Ixvi, 

figs. 12, 13; pl. Ixx, figs. 9—13. 
1871. — — F.J. Pictet and G. Campiche. Foss. Terr. Cret. 

Ste. Croix (Mater. Pal. 

Suisse, ser. 5), p. 280, 

pl. elxxxvi, figs. 1 — 11. 

? — — BoussiNGAULTii, W. A.Ooster. Protozoe Helvetiea, vol. ii, pp. 

106, 127, 141, pl. xvi.figs. 5— ,7. 
?1884. — (Exogyea) SPIRALIS, 0. TTeeri/t. Die Fauna des Ncoconi. im 

Teutoburg. Walde (Palaeont . 
Abhandl., vol. ii), p. 56, pl. ix. 
figs. 13, 14 (y 12). 
? 1892. ExooTRA TUBERCULiFERA, 0. Behrendsm. Zeitschr. d. deutseh. geol. 

Gesellsch., vol. xliv, p. 25. 
? — — ^VBVLickTK, Behrendsen. Ibid., p. 26. 

1895. — — G. Maas. Ibid., vol. xlvii, p. 270. 

— — SPIRALIS, Maas. Ibid., p. 270. 

1896. - TUBERCULIFERA, A. Wolhmann. Ibid., vol. xlviii, p. 832. 

1897. — BoussiNGAULTi, K. Gerhardt. Neues Jabrb. fiii- Miu., etc.. 

Beil.-Bd. xi, p. 175, pl. i, fig. 6. 
1900. — TUBERCULIFERA, Wolleniann. Die Biv. u. Gastrop. d. deutseh. u. 

hoUiiud. Neocoms (Abhandl. d. 
k. preuss. geol. Landesanst., N.F., 
pt. 31). p. 13. 
]f»06. — — Wolleniann. Jab rb. d. k. preuss. geol. Landes- 

anst. M. Bergakad., vol. xxvii. 
p. 264. 

53 



406 CRETACEOUS LAMELLIBRANCHIA. 

Non 1842. Exogtra Boussinoaultii, ^. d'Orfcijrjii/. Voy. dans I'Amerique Mcrid., 

vol. iii, pt. 4, pi. xviii, fig. 20 ; 
p , xxi, figs. 8, 9 ( = 0. Minos, 
Coquaud). 

Description. — Left valve very convex, elongated between the ixrabo and the 
postero-ventral extremity, more or less considerably arched, with a sharp carina 
curving from the umbo to the extremity and becoming less prominent on the later 
part of the valve. Behind the carina the valve is concave or flattened, in front of 
it regularly convex. Umbo more or less considerably spiral. From the carina a 
number of rounded radial ribs extend to the margin, but are indistinct or absent 
on the posterior part of the valve ; these give a corrugated margin to the valve ; 
the ribs are crossed by well-marked growth-ridges. Inside the valve, at a sliort 
distance from the margin, is a band of transverse cremxlations. Adductor impression 
large, oval, sulnnedian, or rather near the posterior margin. The attached surface 
maybe small or large; when large, the marginal part (except the posterior) grows 
vertically upwards from the support and bears ribs. Right valve nearly flat, with 
growth-lines ; umbo small, spiral. 

AQinities. — This species is related to i?. if/wo.-*, Coquand,^ but in the latter 
radial ribs occur on the right valve. It seems probable that E. tiihercuHfera has 
been derived from a small form of E. sinuata. A small exam])le (Plate LXI, fig. 
13) which agrees with the Isengata type of E. sinuata, except for the presence of 
radial ribs, seems to connect that species with E. tuber culi/era.^ 

Types. — The type of Koch and Dunker is a right valve fi'om the Neocomian of 
the EUigser Brink ; the surface of this specimen has a tuberculate appearance 
because it is encrusted by another organism.^ Later authors have been able to 
identify it with the forms named E. siihplicata, Romer, and E. BoussiiKjanlti, 
d'Orbigny, of which good figures have been published. The specimens figured by 
Forbes, which have a large surface of attachment, are from Atherfield, and are now 
in the Museum of Practical Geology (No. 25984). 

Distribution. — Lower Greensand: — Perwa-bedof Atherfield, Redcliff (Sandown), 
and East Shalford ; Crackers of Atherfield ; Ferruginous Sands of Shanklin ; 
Hythe Beds of Lympne. 

1 D'Orbigny, ' Pal. Fran9. Terr. Crt-t.,' vol. iii (1847), pi. cccclxviii, figs. 1 — 3 ; Coquand, ' Mou. 
Ostrea, Terr. Crt-t.' (1869), p. 183, pi. Ixiv, figs. 1—3, pi. Ixxiii, figs. 4^-8, pi. Ixxiv, figs. 14, 15 ; Pictet 
and Campiche, ' Foss. Terr. Crt't. Ste. Croix' ('Mater. Pal. Suisse,' ser. 5, 1871), p. 278, pi. elxxxv ; 
Wollemaun, ' Bivalv. u. Gastrop. deutsch. ii. holliind. Neocoms' (1900), p. 15; Miiller, ' Deutsch.- 
Ost-Afrika,' vol. vii (1900), p. 548, pi. xxiii, fig. 1, text-figs. 46, 47. 
- See also Leymerie (184'2), pi. xi, fig. 4. 
3 The name tuberculi/era is consequently inappropriate, hut has [been retained by several authors. 



EXOGYRA. 407 

ExoGYRA coNiCA (Sowevhij), 1813. Text-figures 215—242. 

1813. Chama CONICA. J. Sowerhy. Min. Conch., vol. i. p. 69, pi. xxvi, fig. 3. 

— — HECURVATA, Sowerby. Ibid., p. 69, pi. xxvi, fig. 2. 

— — PLiCATA, Sowerby. Ibid., p. 70, pi. xxvi, fig. 4. 

— — HALIOTOIDEA, Sowerby. Ibid., p. 67, pi. XXV, figs. 1—5. 

1829. ExoGTRA CONICA, /. de C. Sownby. Ibid., vol. vi, p. 219, pi. dcv, figs. 

P 1QQQ . ^ figs- 1 3. 

. IVSi. — CONICA, A. Gofdfuss. Petref. Germ., vol. ii, p. 36. pi. Ixxxvii. 

fig. 1. 

— — SUBCARINATA, Gokl/usS. Ibid., p. 37, pi. IxXXVii, fig. 4. 

— — UNDATA, Goldfuss. Ibid., p. 35, Ixxxvi, fig. 10. 

— — HALIOTOIDEA, GoldfusS. Ibid., p. 38, pi. IxXXViii, fig. 1. 

1837. Amphidonte conica, G. G. PvscJi. Polens Palaont.. p. 39. 
— HALIOTOIDEA, PuscJi. Ibid., p. 38. 

1839. ExOGYRA CORNU ARIETI.S, E. HALIOTOIDEA ft E. AQUILA. H. B. Gehlifz. 

Char. d. Schicht. u. Petref. des siichs. 
Kreidegeb., pt. 1, p. 20. 

1840. — PLicATCLA, Geinitz. Ibid., pt. 2, p. 84. 

. 1846. — _ A. E. Reuss. Die Versteiu. der bohm. Kreideformat, 

pt. 2, p. 44, pi. xxxi, figs. 5 — 7. 
1847. OSTREA CONICA, A. d'Orbigny. Pal. Fran?. Terr. Cret., vol. iii, p. 726, 

pi. cccclxxviii, figs. 5 — 8 ; pi. cccclxxix. 
figs. 1—3. 

— — Eauliniana. d'Orbigny. Ibid., p. 708, pi. cecclxxi, figs. 1—3. 

— — HALiOTiDEA. fZ'Or&i;/".'/- Ibid., p. 724, pi. eccclsxviij, figs. 1 — 4. 

1849. Grtph^a CONICA, r. i?ro«;w. Illustr. Fobs. Couch. Gt. Brit, and Ireland. 

p. 149, pi. Ix, fig. 3. 

— — HALIOTOIDEA, Browtt. Ibid., p. 149, pl. Ix, figs. 6—9. 

1850. OsTREA CONICA, A. d'Orbigny. Prodr. de Pal., vol. ii. p. 171. 

— — Eauliniana, d'Orbigny. Ibid., p. 1,39. 

— — HALIOTIDEA, rf'0r6i(/Hy. Ibid., p. 171. 

— ExoGYRA Eauliniana. J. de C. Sowerby. in F. Dixon. Geol. Sussex, p. 357. 

{E. haliotoidea, p. 386. ed. 2), 
pl. xxvii, fig. 7. 
CONICA. H. B. Geinitz. Das Quadersandst. oder Kreidegeb. in 

Deutschlaud, p. 202. 

1853. OsTREA Eauliniana. F. J. Piclef and W. Rou.t. Moll. Foss. Gres verts de 

Geneve, p. 521. pl. 1, 
fig. 1. 

1854. ExOGYRA CONICA, J. Morris. Cat. Brit. Foss., ed. 2, p. 166. 

— — HALIOTOIDEA. Morris. Ibid., p. 166. 

^^^^- "~ — ''' Wiltshire. Eed Chalk of England (Geol. 

Assoc), p. 16, pl. ii, fig. 6. 

— OsTREA VESXcuLABis, Wiltshire. Ibid., p. 16. pl. ii. fig. 5. 

1863. — CONICA, A. V. Strombeck. Zeitschr. d. deutscb. geol. Gesellsch., vol. 

XV, p. 109. 



408 CRETACEOUS LAMELLIBRANCHIA. 

? 1868. OsTREA CONICA, A. BriaH and F. L. Cornet. Meiile de Bracquegnies (Mcui. 

cour. et Mi'm. des. Sav. I'traiigers, vol. xxxiv), p. 45. 
pi. iv, figs. 3, 4. 

— — HALiOTOiDEA, BriaH andCornet. Ibid., p. 45, \A. iv, figs. 5, 6, 8. 
? 1868. ExooYRA CONICA, E. Eichwald. Lethsea Rossioa, vol. ii, p. 400. 

1869. OsTREA CONICA, H. Coqvand. Mon. Ostrea, Terr. Cn't., p. 160, pi. liii, 

figs. 1—7. 

— — HAMOTIDEA, Coquand. Ibid., p. 144, pi. 1, figs. 8—10; pi. lii, figs. 

11—17. 

— — Rauliniana, C'o3«anrf. Ibid., p. 157, pi. Ixi, figs. 1—3. 

? 1871. ExoGYRA HALIOTOIDEA, F. SfoHczka. Palseoiit. Indica, Cret. Fauua S. 

India, vol. iii, p. 458, pi. xxxvi, 
fig. 7 ; pi. xxxvii, figs. 1 — 3. 

1871. Ostrea Eauliniana, F. J. Ficfet and G. Campiche. Terr. Crct. Ste. 

Croix (Mater. Pal. Suisse, ser. 6), p. 307, 
pi. exciii, figs. 15, 16. 

— — CONICA, Pictet and Campiche. Ibid., p. 302, pi. exciii, figs. 1, 2. 

1872. — (Exooyra) CONICA, H. B. Geiiiitz. Das Elbthalgeb. in Sachsen 

(PaliEontographica, vol. xx, pt. 1), 
p. 183, pi. xl, figs. 8—13 ; pt. 2, pi. 
viii, fig. 14. 

— — — HALIOTOIDEA, Geinitz. Ibid., p. 184, pi. xli, figs. 1 — 13. 
1875. ExoGYRA HALIOTOIDEA, A. J. Jukes-Bmwne. Quart. Journ. Geol. See, 

vol. xxxi, p. 296. 
? 1877. — CONICA, A. Frilsch. Stud, im Gebiete der bohm. Kreideforniat. ii. 

Weissenberg. u. Malnitz. Schiclit., p. 139, 
fig. 184. 
1878. Rhynchostreon conicum, J?. J?ay?e. Explicat. Carte gcol. France, vol. iv, 

Atlas, pt. 1, ]>1. cxxxviii, figs. 6, 7. 
1881. Ostrea conica, J. Gosselet. Esquisse gi'ol. du Nord, iii, pi. xvii, fig. 11. 
? 1882. ExoGYRA conica, H. Schroder. Zeitschr. d. deutsch. geol. Gesellsch., 

vol. xxxiv, p. 259. 

— — — G. Seguenza. Atti R. Accad. Lincei, ser. 3, CI. Sci. Fis. 

Math., vol. xii, p. 176. 

— — haliotidea, Seguenza. Ibid., p. 175. 

1883. — conica, vars., W. Keeping. Foss., etc., Neoo. U]iware and 

Brickhill, p. 101, pi. iv, fig. 3. 
? 1885. — — F. Nolling. Die Fauna d. baltisch. Cenoman. (Palaeont. 

Abhandl., vol. ii), p. 14, pi. ii, figs. 1, 2. 
1890-91. Ostrea conica, A. Perov. Brachiopodes etc., Terr. Cn't. Hauts- 

Plateaux de la Tunisie, p. 113, pi. xxiii, 
figs. 8—10. 
? 1893. Ostrea sp. ef. haliotoidea, R. Michael. Zeitschr. d. deutsch. geol. 

fxesellsch., vol. xlv, p. 239. 
1895. ExoGYRA conica, E. Tiessen. Ibid., vol. xlvii, p. 466. 
? — — (•/. haliotidea, Tiessen. Ibid., p. 465. 

1909. — conica, B. B. Newton. Trans. Eoy. Soc. S. Africa, vol. i, p. 51, 

I'l. ii, figs. 8—10. 



EXOGYRA. 4o<.i 

Non 1827. Chama conica, 8. Nilsson. Petrific. Suecaua, p. 28, pi. viii, tig. 4. 
— 1837. — — W. Hisinger. Lethaea Suecica, p. t)3, pi. xix, fig. 4. 

? — 1841. ^■s.oGYRA conic A, F. A. liijmer. Die Verstein. d. uoid-ileutscli. Kreidegcb., 

p. 47. 
? _ 1883. — —A. Frifsch. Stud, ini Gebiete d. bohin. Kreidef. iii 

Iserschicht., p. 117, fig. 92. 

Description. — Left valve very convex, with a more or les.s subtriangular or 
semi-oval outline, vei'y inequilateral. Anterior and ventral margins rounded ; 
posterior margin oblique, either straight, slightly concave, convex or sinuous, often 
forming a rounded angle with the ventral margin. Umbo spiral, curved inward.s, 
and considerably backwards ; the attached surface usually behind the umbo. A 
carina, generally distinct but sometimes rounded, extends in a curve from the umbo 
towards the postero-ventral extremity. The part of the valve behind the carina 
is more or less flattened, and may be concave near the umbo ; the part in front of 
the carina is regularly convex. In large specimens the postero-ventral part 
is more extended and the length of the shell in relation to the height becomes 
I'elatively greater, the postero-ventral extremity is more rounded, and the 
carina becomes less distinct. The surface of the valve is usually smooth, exce]>t 
for growth-lines, bi;t in some specimens {nndafa form) numerous somewhat 
irregular radial ridges are present, either in the neighbourhood of the umbo or 
over the entire valve. On the inside of the valve, at a short distance from the 
margin, is a band of small transverse ridges and pits which broadens and becomes 
more irregular near the postero-dorsal margin. Adductor impression rather near 
the postero-dorsal margin, with its upper boundary straight or slightly convex. 

Right valve thin, operculiform, often slightly concave, with a small spiral 
umbo ; surface nearly smooth ; outline varying with that of the left valve. 

In the forms described above (conica type), the surface of attachment is 
small, but it may be very large so that all the left valve Avith the exception of a 
narrow marginal part is fixed {hal iofoidea and Raullninna types) ; between these 
extremes every gradation is found. The free marginal part, which .■seldom extends 
to the posterior border, usually grows nearly vertically upwards from the bod}- to 
which the shell is attached. When the attached surface is mainly or entirely 
behind the position of the carina, then the free marginal part in front is larger, and 
usually the shell is relatively higher and the spire of the umbo less developed, and 
in such cases the marginal part sometimes forms an acute angle with the attached 
surface.' The character of the surface (flat, concave, convex or irregular) to which 
the left valve is attached also influences the form of the shell. 

AJialties. — The forms of small or moderate size, which are abundant in the 

1 See d'Orbiguy, pi. cccclxxviii, figs. 1 — 4. 



410 CRETACEOUS LAMELLIBRANCHIA. 

Upper Greensand, and of wliicli typical examples were figured by Sowerby in 1829, 
have a small surface of attacliment, and have been known in this country as E.rogijra 
rnnicd (figs. 220 — 225). A similar form, but of larger size, is common in the 
Clialk Marl (figs. 228, 229), and the Glauconitic Sandstone of Antrim; no line can 
be drawn between this and the smaller form of L'. conira, with which it has been 
united by most authors (e.g. d'Orbigny, Morris, Coquand, Bayle, Peron) ; examples 
indistinguishable from ]<]. cuiiica of the Upper Greensand are associated with the 
larger form in Antrim, and on the other hand, some specimens found in the Upper 
Greensand of the south of England are of larger size than the majority of examples 
and cannot be separated from the larger form of J'J. conica ; but nevertheless the 
larger form appears generally to mark a someAvhat higher horizon than the 
smaller (conica, Sowerby) form. 

E. haliotoiJea, Sowerby, from the Upper Greensand (fig. 2-40), is a small form 
of E. conica with a large surface of attachment, and is connected by intei'mediate 
forms with examples having only a small attached surface. Similarly E. Rauliniana, 
d'Orbigny (fig. 23G — 239), from the Gault, Upper Greensand, and Lower Chalk, 
is a large form of E. conica with a large surface of attachment and is linked by a 
series of gradations (figs. 230 — 235) to the type with only a small attached 
surface. Peron' has already shown that the large specimens from the Cenomanian 
of France figured as E. ha.liotoideahy d'Orbigny and Coquand are only forms of 
E. conica modified by having a large surface of attachment; they occur in the 
same beds as undoubted examples of E. conica. In some specimens with a large 
attached surface the height of the shell is greater than usual, but this, as pointed 
out above, is due to the shell being fixed mainly or entirely by the posterior 
slope behind the carina; in such cases the free marginal part forms a sharp angle 
with the attached surface. Morris and Jukes-Browne united E. haliotoidea and 
E. Bauliniana, and Pictet and Campiche recognised the very close relationship 
of these two forms. 

Examples from horizons above the Cenomanian have been refeired to E. haiiu- 
foidea by some authors,' notably Hennig, who has compared the Senonian forms 
of Sweden with specimens from the Cenomanian and Gault. Without the oppor- 
tunity of examining the Senonian forms I am unable to express any opinion as to 

V'Compte Eeud. Assoc. frau9. Avauc. Sci.,' xxxvi (1908), pt. 2, p. 312. 

2 Chama haliotoidea, Nilsson, Petrifie. Suecaua (1827), p. 28, pi. viii, fig. 3 ; Hisinger, ' Letbijea 
Suecica' (1837), p. 62, pi. xix, fig. 3. Exogyra haliotoidea, Eeuss, ' Die Verstein. d. hiiliui. Kreidefonnat.,' 
pt. 2 (1846), p. 44, pi. xxvii, figs. 6, 9, 10, pi. xxxi, figs. 9—10; Miiller, 'Petrefact. Aachen. Kreidef., 
l.t. 1 (1847), p. 42 ; Scliroder, 'Zeitsclir. d. deutsch. geol. Gesellsch.,' vol. xxxit (1882), p. 260, pi. xv, 
fig. 5; Griepenkerl, 'Pala>ont. Abbandl.,' vol. iv (1889), p. 36; Hfiniig, 'Kevis. Lamellibr. i Nilsson's 
' Petrifie. Suecana ' (1897), p. 19, pi. i, fig. 20, pi. ii, figs. 3, 4; Rutot, ' Bull. Soc. Beige Gi'ol. Pal. et 
Hydrol.,' vol. x (1897), p. 27, fig. 11. 



EXOGYRA. 



41] 




230 



231 



Fios. nry—2ai.—Exogyraconica (Sow.). 215-226, Upper GrcensanU. 227— 231, Chalk Marl. SedRwick 
Miiseuiii except 219, 224, 22S. 215, 21(5, Niton : left and right valves. 217, 21S, Vontnor ; loft and 
right valves. 2I'.I, Ilalilon ; Rritish JIuseum. No. L. UiSCO ; loft valvo of rihiiod variety. 220— 22;{. 
zone of Hchlwnhachiii rosti-a/u, Ulackdown ; loft valves. 222, riglit valve of 221. 221, zone of 
I'ecten asper, "Warminster; Hristol Miisoiini ; loft valve. 225, zone of P. aspcr, Evei-shot; left 
valve. 226, zone of Sr/i(a;Hfcnc/ii(i i-o«()-<i(ii, Dunscombo; loft valve. 227, Folkestone; left valvo. 
228, 22il, Blvie Bell Hill, Hurham ; British .Museum, No. L. 1U382; left valvo and doi-sal view. 
230, 231, Kolkostone ; left v;ilve and dorsal view. All natural size. 



412 



CRETACEOUS LAMELl.IBRANCHIA. 



their velationsliip. Hennig also includes E.auricnlitris (Walilenberg)' in E. halio- 
tot'dea. 

Pictet and Campiclie figure and describe exam^^les of E. conica from the Aptian. 
Specimens of E.ro/ii/rn fi'om the Lower Greensand of Upware, Brickhill, Faringdon 
and Slianklin have becMi referred to H. conica; in these the carina is more rounded 




233 



239 



Figs. 232—242. — Exoqyra conica (?to\\\). Sedf^wkk Museum oxeept 23S— 240. 232—235, Cambridge 
Greensand (base of Chalk Marl). 233, 231-, loft valves. 232. rifjbt valve of 233. 23.5, rifrht valve 
of 234. 23(), 237, zone of Holaster xubglubosus, Burwell ; 230, right valve : 237, anterior view of 236 
showin-j the large size of the attached surface of the left valve. 238, 239, Gault, Folkestone ; 
Museum of Praitical Ueology, No. 20873 ; 238, right valve ; 239, anterior view showing left valve 
attached to a flat Inoccramus. 240, Upper Greensand, Devizes. Museum of Practical Geolog>', 
No. 20999. Left valve. 241, 242, Cambridge Greensand; ribbed form with a large surface of 
attachment ; 241, left valve; 242, anterior view of 241. All natural size. 



than in the common form of the species, but thej agree closely with, and seem to 
be inseparable from some forms of E. rovira from the Upper Greensand (figs. 
215-218). 

Small specimens with radial riljs (fig. 219), such as the one figured by Goldfuss 

^ 'Petrific. tell. Suec' (1821), p. 58. See also Schroder, ' Zeitscbr. d. deutsdi. gcol. Gesellscli.,' vol. 
xxxiv (1882), p. 260, pi. xv, fig. 4. 



EXOGYRA. 413 

as E. imdata and by d'Orbigny as E. conica, have not usually been regarded 
as distinct from E. conica. 

Pictet and Campiclie record E. aniiiennensis (d'Orbigny)^ from the Upper 
Greensand of Blackdown, but they doubt whether that form is really distinct from 
E. conica; the chief difference is that in the former the left umbo is less prominent 
and less curved. 

E. subconica, Vogel von Falckenstein,^ from the Senonian is allied to E. conica. 

Types. — The types from the Upper Greensand are in the British Museum. 
Chama conica from Chute (Warminster) ; G. recurvata and G.plicata from Haldon; 
€. haliotoidea (figs. 1, 3, 5 are missing) from St. Mary Donhead (Wiltshire). The 
specimens of E. conica figured by Sowerby in 1829 from the Upper Greensand of 
Blackdown, and the specimen figured in Dixon as E. liauUniana from the Lower 
Chalk (probably zone of Holaster subglohosus) of Sussex, are in the same Museum. 
The specimens from the Lower Greensand of Upware, figui'ed by Keeping, and 
those from the Red Limestone of Hunstanton figured by Wiltshire, are in the 
Sedgwick Museum. 

Distribution. — Probably Lower Greensand of Upware and Faringdon. Lower 
and Upper Gault of Folkestone. Lower Gault of the Isle of Wight. Red Lime- 
stone of Hunstanton. Upper Greensand (zone of SclilcenbacJna rostnita) of 
Blackdown, Haldon, Dunscombe, Beer Head, Pinhay Cliiis, Niton, Ventnor, etc. 
Upper Greensand (zone of Pecten asper) of Bvershot, Eggardon Hill, Warminster, 
the Dorset coast, and the Isle of Wight. Cambridge Greensand (indigenous and 
derived). Chloritic Marl of Compton Bay, Isle of Wight. Chalk Marl (zone of 
Schloenbachia varians) of Folkestone, Blue Bell Hill (Burham), Reach and Stoke 
Ferry. Cenomanian of Wilmington, Devon, and the South Devon coast. Zone 
of Holaster si(bglobosus of Burham, Holborough, Dover, Arlesey, Burwell and 
Fulbourn. 



ExoGYEA COLUMBA {Lamarclr), 1819. Text-figs. 243—248. 

1768. G. W. Knorr and J. E. M. WalcJi. Eecueil Mon. Catastr. P^trificat., 

vol. ii, p. 127, pi. D III, C, 
figs. 1-3. 

1802. GrtphjEA subobbiculata, Lamarck. Systeme Anini. saus Vert., p. 398. 
1813. Grtphites RATI8B0NENSIB, E. T. V. SchloUieim. In Leonhard's Taschen- 

buch fiir Miu., vol. 

vii, p. 105. 

• 'Pal. Fran9. Terr. Cret.,' vol. iii (1847), p. 711, pi. cccclxii, figs. 1—4. Pictet and Canipiche, ' Terr. 
Cret. Ste. Croix' (1871), pp. 304, 308, pi. cxciii, fig. 3. 

- 'Zeitschr. d. deutsch. geol. Gesellsch.,' vol. Ixii (1911), p. 5G0, fig. 1. 

54 



414 CKETACEOUS LAMELLIBRAXCHIA. 

1819. GrtpH/EA. columba, Lamarck. Anim. saus Vert., vol. vi, p. 198. 

1820. Grtphites spiratus, E. T. v. Schlofheim. Petrefactenk., p. 28S (lutrtim). 

1821. GRTPHiEA COLUMBA, M. J. L. De/ratice. Diet. Sci. nat., vol. xix, p. 534. 

1822. — — J. de C. Soiverhj. Min. Conch., vol. iv. i\ llo. 

pi. ccclxxxiii, ti<ifs. 1, 2. 

— Grtphea columba, a. Broiujniart. lu C'uvier, Ossemeus Fossiles, vol. ii, 

pp. 320, 608, pi. vi, fig. 8. 

1832. OsTREA columba, G. p. De><hayes. Hist. nat. Yers et Mollusques (Encvcl. 

method.), vol. ii, p. 302, Planches, 
vol. iv, pi. clxxxix, figs. 3, 4. 

1833. ExoGYRA columba, a. Gol(Ifu!>s. Petref. Germ., vol. ii, p. 34, pi. ixxxvi, fig. 9. 
1837. — — A. d'Arrhinr. Mc'm. Soc. geol. de Finance, vol. ii, p. 185. 

— Grtph,ea columba, F. Dujardin. Ibid., p. 228. 

— Amphidonte C01.HWB&., G. G. Ptisch. Polens Paliiont., p. 37,pl. v, figs. 1,2. 
1839. ExoGYRA columba, H. B. Geinitz. Char. d. Schieht. u. Petref. des siiehs. 

Kreidegeb., pt. 1, p. 20. 
1841. — (GRYPH.ffi;A) COLUMBA, F. A. Bimer. Die Yerstein. d. nord- 

deiitseh. Kreidegeb. 
p. 46. 

1846. — COLUMBA, H. B. Geinitz. Grundr. d. Yerstein., ]i. 481, pi. xx, 

figs. 19, 20. 
? — — ■ — A. E. Beuss. Die Yerstein. der bijhm. Kreideforniat.. 

pt. 2, p. 43, pi. xxxi, figs. 1 — 4. 

1847. OsTREA COLUMBA, A. d' Oi-hifjii ij. Pal. Franc. Terr. Cret., vol. iii.p. 721, pi 

cccclxxvii. 
1850. — — d'Orhiijny. Prodr. de Pal., vol. ii, p. 171. 

— ExoGYEA COLUMBA, H. B. Geiiiitz. Das Quadersandst. oder Kreidegeb. in 

Deutschland, i>. 2U2. 
1851-52. ExoGYRA COLUMBA, H. G. Bronn. Letha;a Geogn., vol. ii, pt. 5. p. 270„ 

pi. xxxi, fig. 10. 
1854. — — /. Morris. Cat. Brit. Foss., ed. 2, p. 166. 

1857. — — J.EiralJ. Zeitschr. d. deiitsch. geol. Gesellsch., vol. ix, 

p. 12. 
1859. OsTREA Eeaumuri, H. Coquand. Bull. Soc. gcol. de France., ter. 2, vol. 

xvi, p. 960. 
? 1866. OsTEEA cfr. COLUMBA, A'. A. Zittel. Bivalv. d. Gosaugeb. (Denkschr. d. 

k. Akad. d. Wissensch., Wien, 
Math. -nat. Classe, vol. xxv, pt. ii), 
p. 47 [123], pi. xix, fig. 2. 
?1868. Ostrea COLUMBA,^. Briart and F. L. Cornet. Meule de Bracquegules 

(Mem. eour. et Mem. 
des. Sav. etrangcrs, 
vol. xxxiv), p. 46, pi. 
iv, figs. 13 — 15. 

— ExOGYRA COLUMBA, E. EicJnraJd. Letli»a Rossica., vol. ii, p. 404. 

1869. OsTREA eatisbonensis, H. Coquand. Mon. Ostrea, Terr. Cret., p. 121, pi. 

xlv, figs. 8—12. 



KXOGYRA. 415 

? 1870. OsTREA coLUMBA, W. A. Oonter. Protozoe Helvet., vol. ii, p. 57, pi. x, 

fig. 18. 
— ExoGYKA coLUMBA, F. Bi'imei: Geol. v. Oberschles., p. 332, pi. xxvi, fig. 1. 

1871. OsTRKA COLUMBA, F. J. Piclet and G. Camjnche. Foss. Terr. Crt't. Ste. 

Croix (Matt'r. Pal. 

Suisse, ser. 5), p. 319. 

■ — ExoGYRA suBORBicDLATA, F. StoUczka. PaliBout. Iiidica, Cret. Foss. S. 

India, vol. iii, p. 462, pi. 
xxxv, figs. 1 — 4. 

1872. OsTREA (Exogyra) colujiba, H. B. Geinitz. Das Elbtbalgeb. in Sachsen 

(Palaeontographica, vol. 
XX, pt. 1), p. 181, \<\. xl, 
figs. 4 — 7. 

1877. ExoavRA col,v:!.iba, A. Fritscli. Stud, ini Gebieteder bobm. Kreidefoiinat., 

ii. Weissenberg. u. Malnitz. Sehicbt., 
p. 139, fig. 135. 

1878. Rhynchostreon Chaperi, E.Bayle. Explicat. Carte geol. France, vol. iv, 

Atlas, pt. 1, pi. cxxxviii, figs. 1 — 5. 
1882. Exogyra ratisbonensis, G. Seguenm. Atti R. Acead. Liucei, ser. 3, CI. 

Sci. Fis. Matb., vol. xii, p. 181, 
pi. xix, fig. 1. 
1890-91. OsTREA suBORBicuLATA, A. PeroH. Descript. Braeh. etc., Terr. Crt't. 

Tuuisie, p. 119. pi. xxiii, figs. 
11—13. 
1893. OsTREA COLUMBA, S. Meutiier. Le Naturaliste, p. 176, fig. 3. 
— Exogyra columba, R. Michael. Zeitscbr. d. deutscb. geol. Gesellscb., 

vol. xlv, p. 238. 
y — _ svBOit.Bicvi..KT\, T. W. Stanton. Colorado Formation (Bull. U.S. 

Geol. Survey, No. 106), p. 
62, pi. V, fig. 6 ; pi. vi, fige. 1, 
2 ; pi. viii, fig. 1. 
1897. — COLUMBA, R. Leonhanl. Palaeoutograpbica, vol. xliv, p. 27. 

_ _ — V. Sohle. Geogn. Jahresb. (1896),p. 41. 

9 1900. — — G. Mailer. Deutscb-Ost-Afrika, vol. vii, p. 566, pi. 

xxiv, fig. 2. 

1902. — P. Ojtpenhehn. CentralM. fiir Min., t'tc., p. 500. 

1903. OsTREA SUBORBICULATA, R. Fortau. Bull. Inst, flgjptieu, ser. 4, vol. iv, 

p. 289. 
1911. Exogyra columba, 0. Schlagintweit. Neues Jabrb. fiir Miu., etc., Beil.- 

Bd. xxxiii, ]>. 111. 

Deacnptioii.—HlxeW very inequivalve, moderately or rather considerably inecpii- 
lateral, iisnally higher than long and more or le.ss ovate in outline, with, in some 
cases, the postero-ventral margin somewhat produced. 

Left valve inflated, usually with a very small surface of attachment. Umbo 
usually prominent, spiral, curved more or less considerably backwards. The 
flank of the valve may be regularly convex, or may show a rounded carina 



416 



CRETACEOUS LAMELLIBRANCHIA. 



extending from the umbo postero-ventrall}-, but this often l)econies indistinct in 
the later stages of growth ; the posterior part of the valve (behind the carina) is 
convex, except the postero-dorsal part near the uml)o, which is concave, and here 
the margin is more or less concave. The surface of the valve is smooth, except 




246 



247 



248 



Figs. 243 — 2-iS. — Ennijyru columba (Lam.). Zone of Pecten asper. 243 — 24o, Kversliot. 246 — 24S, 
Eggardon Hill. 243—247, left valves. 244, posterior view of 243. 248, right valve and left 
umbo of 247. Sedgwick Mnsenm, Cambridge. All x |. 

for growth-lines. Right valve flat, or slightly convex or concave, sometimes 
undulating. Umbo small, spiral. 

Affinities. — This species is allied to E. conica, but the carina is less distinct 
and more rounded, the posterior part of the left valve is less flattened, and the 
spire of the left umbo is better developed. 

Bemarls. — Since the name given by Lamarck in 1819 (columha) has been used 
by the majority of later writers it seems better to retain that, rather than attempt 
to revive the little-known name given b^- the same author in 1802. 



EXOGYKA. 417 

In tlie Cenomaniaii of France and other regions where this species is very 
abundant it is found to be much more variable than it is in the South of England. 
This variation is also seen in the specimens found in the Glauconitic Sandstone 
of Antrim. Variation is particularly noticeable in the size of the left umbo, in the 
extent of its curvature, the more or less inequilateral character of the shell and in 
the distinctness of the carina.^ 

In the Cenomanian of Algeria and Tunis, specimens, usually known as Ostrec 
Meriiieti, Coquand,* are extremely abundant and very variable ; but Peron, after 
comparison with numerous French specimens from the same horizon, refers these 
North African forms without doubt to E. columha. 

Types. — From the Cenomanian of Le Mans. The specimens figured by Sowerby 
are in the British Museum ; fig. \ (upper figure) and fig. 2 are from the Ceno- 
manian of Le Mans; fig. 1 (lower figure) is probably from the same locality 
although labelled " Northampton." 

Distribution. — Upper Greensand (zone of Schloenhachia rostrata) of Blackdown, 
the South Devon and Dorset coasts. Upper Greensand (zone of Pecten asper) of 
the South Devon and Dorset coasts, Evershot, Askerswell, Eggardon Hill, Little- 
bredy (Dorset) and AVarminster. Chloritic Marl of Compton Bay, Isle of Wight. 
Cenomanian (Meyer's beds 11, 12) of Beer Head. 



ExoGTRA DiGiTATA {Sowrrhij), 1817. Text-figs. 249—252. 

1817. Chama DIGITATA, J. Sowerhij. Mill. Conch., vol. ii, p. 165, pi. thxiv, figs. 

1—4. 
1840. ExooYRA LACINIATA. H. B. GeinUz. Char. d. Schicht. u. Petref. des siiths. 

Kreidegeb., pt. 2, p. 58. 

1849. GkyphjEA DIGITATA, T. Browii. Illustr. Foss. Conclj. Gt. Brit, and Ireland, 

p. 149, pi. Ix, fig. 16. 

1850. ExoGTRA DIGITATA. H. B. Geiititz. Das Quadersandst. oder Kreidegeb. in 

Deutscliland, p. 204. 
1854. _ — /. Morris. Cat. Brit. Foss., ed. 2, p. 166. 

1862. OsTREA CoQUANDi, JuUeii, in H. Coquand, Geo . et Pal. Constantlne, pi. 

xxxiii, figs. 10 — 12. 



1 It should be noted that the apparently small size of the left umbo in the specimens figured by 
some authors (e. g. Geiuitz) is due to the fact that the specimens are internal casts from which the 
thick shell has been removed. 

« 0. Mermeti, Coquand, ' Geol. et Pal. Reg. sud Prov. Constantine ' (1862), p. 234. pi. xxiii, figs. 
3—5 ; Coquand, ' Mon. Ostrea, Terr. Cret.' (1869), p. 131, pi. Hi, figs. 10—12 ; Lartet, ' Annal Sci. g^ol., 
vol. iii (1873), p. 60, pi. i, figs. 8—16. 0. Larteti, Coquand, op. cit. (1869), p. 153, pi. Ixii, figs. 15, 
16. 0. Luynesi, Lartet, oji. cit. (1873), p. 64, pi. x, figs. 17, 18; Coquand, oj>. cit. (1869), p. 153. 
pi. ixii, figs. 17, 18. 



418 



CKETAC'KOU.S I.A.AIEI.I.IHHANCHIA. 




Figs. 249 — 2o2.—Exogyra digitata (Sow.). Upper Greensand (zone of Pcc/en asjjec). Left valves. 249, 
near Lyme Regis ; British Museiun, No. 52. 250, White Nothe ; British Museum, No. L. 4914. 251, 
Evei'shot; Museum of rractical Geology, No. 20956. 252, Weston, South Devon; Sedgwick 
.Museum ; convex variety. All x J. 



1868. OsTREA DIGITATA, A. Biiait and F. L. Cornet. Meule Je Bracquegnies 

(Mtm. com-. etMciu. des 
Sav. I'trangers, vol. 
xxxiv), p. 47, pi. iv, figs. 
1.2. 

1869. — — H. Coqiiand. Mon. Ostrea, Terr. Crot., p. 142, j-l. xli, 

figs. 6 — 8. 
1871. — —F.J. Piriet and G. Campiche. Foss. Terr. Crct. Ste. 

Croix (Mater. Pal. 
Suisse, ser. 5), p. 317. 



EXOGYRA. 419 

1872. OsTREA (Esogtra) digitata, H. B. Geinifz. Das Elbthalgeb. in Sachseu 

(Palteontograpliica, vol. 
x.\-, pt. 1), p. 184, pi. xl, 
fig. 14. 

1882. Exooyra digitata, G. Seyuenza. Atti R. Accad. Lincei, ser. 3, CI. Sci. 

Fis. Math., vol. xii, p. 180. 

Descript ill It. —^heW inequilateral, with rounded outline; height and lengtli 
often nearly e([ual. 

Left valve moderate]}', s(Mnetinies con.sideral)ly convex. Umbo spiral, curved 
considerably backwards ; the attached snrface small, and posterior to tlie umbo. A 
carina, sometimes sharp, sometimes roimded, extends in a cnrve from the nmbo 
towards the postero-veutral extremity, and becomes less distinct on the later part 
of the valve ; behind the nmbo the valve is concave or flattened. A few prominent, 
widely separated radial folds are present ; some start from the carina, others 
begin later, and the ventral part of the carina sometimes becomes replaced by a 
fold. The dorsal folds are curved. On the folds strong spine-like projections are 
often developed, and form projections at the margin of the valve. Fine growth- 
lines occur, and bend over the folds. Right valve nearly flat. 

Affinities. — 0. vnJtur, Coquand,' resembles this species in its strong folds and 
spines, but the left valve is more inflated and the carina less distinct. E. digifafa 
shows considerable resemblance to some forms of E. cornu ariiiis (Xilsson)' from the 
Senonian, in which is included E. laciniafa (Xilsson). 

Except for the strong radial folds E. digitota resembles some of the less convex 
forms of E. sinnafit, from which it may have been derived. 

Tijpe. — The types, from the Upper Greensand (zone of Pecten asper) near 
Sidmouth, cannot be found. 

DistribufioH. — Upper Gi-eensand (zone of Fecfen asper) of Beer, Weston 
(Devon), Evershot, and White Notlie (Dorset). 



ExoGVEA siGMOiDE.v, Reuss, 1844. Plate LXI, fig. 12. 

1844. EsoGYRA SIOMOIDEA, A. E. lieiiss. Geoguost. Skizz. Biihtuen, vol. ii, 

p. 180. 
1846. — — A. E. Eeiiss. Die Versteiu. derbohiu. Kreidefoniiat.. 

pt. 2, p. 44, pi. xxvii, figs. 1 — 4. 

' ' Men. Ostrea, Terr. Cr^t.* (1869), p. 118, pi. xxxix, figs. 1 — 4. Rhynchostreon nilhir, Bavk-, 
' Exp'ical. Carte gcol. France,' vol. iv (1878), Atlas, pl.cxli. 

= Nilsson, ' Petrifie. Suecana' (1827), p. 28, pi. viii, fig. 1. Griepenkerl, ' Palaeont. Abhandl.,' v..I. 
iv (1889), p. 35, pis. V, vi, vii, figs. 6, 7, Heniiig, 'Revis. Lamellibr. i Nilssou's Petrifie. Suecana' 
(18;t7), p. 21. Chama laciniata, Nilsson, o^). cit., p. 28, pi. viii, fig, 2. 



420 CRETACEOUS LAMELLIBRANCHIA. 

? 1866. OsTREA (Exooyra) 8p. cfr. siomoidea, K. A. Zittel. Bivalv. d. Gosaugeb. 

(Denkschr. d. k. Akad. Wissensch. 
Wien, Math.-nat. CI., vol. xxxv, 
pt. 2), p. 123, pi. xix, fig. 5. 
1869. — SIOMOIDEA, H. Coqnand. Mon. Ostrea, Terr. Crt't., p. 93, pi. xxxiv. 

figs. 5 — 7 bis. 
1872. — (Exooyra) siomoidea, H. B. Geinitz. Das Elbthalgeb. in Sachsen 

(Palaeontogniphica, vol. 
XX, pt. 1), p. 186, pi. xli, 
figs. 14—27. 
? 1882. Exooyra cfr. siomoidea, B. WiiidnuJller. Jahrb. d. k. preuss. geol. 

Laudesanst. fiir 1881, 
p. 30. 
1888. — siomoidea, G. Midler. Ibid, fiir 1887, p. 401. 

1911. — — A. Fritsch. Stud, im Geb. d. biilimisch. Kreidef., 

Korycaner Schicht., p. 46, fig. 209. 

Remarls. — The only English specimen I have seen is a right valve collected by 
Mr. LI. Treacher. The strong carina, the concentric ribs on the anterior slope, 
the more sinuous and more oblique posterior margin and growth-lines distinguish 
this species from the Rauliniana form of E. ronlca. The inner margin of the 
valve is finely crenulate. The types came from the Lower Planer-kalk of Schilling 
near Bilin. 

Distribution. — Zone of Micraster cor-ang iiinum of Boxford, Berkshire.^ 



Family— UABIOLITIBJE, Gmij. 
[Omitted from Vol. II, p. 210.] 

Genus — Dukania, H. Douville, 1908. 

■(' Bull. Soc. gcol. de France,' ser. 4, vol. viii, p. 309, and ' Mi'm. Soc. geol. de France, Palt'out.,' vol. 

xviii, 1910, p. 23.) 

DuRANiA MoiiTONi (Mantell), 1833. 

1833. HiPPDBiTES MoRTONi, G. Mantell. Geol. S.E. England, p. 130. 
1836. CoNiA, R. Hudson. Loudon's Mag. Nat. Hist., vol. ix, p. 104, fig. 19. 
1838. Sph^rulites Mortoni, /. E. Gi-ay. Mag. Zool. Bot., vol. ii, p. 228. 
1850. Hippurites Moetoni, /. de C. Sotverhy, in F. Dixon. Geol. Sussex, p. 354 

(p. 386, ed. 2), pi. 

xxvi, figs. 1, 2, 4. 

1 White and Treacher, 'Quart. Journ. Geol. Soc.,' vol. Ixii (1906), p. 618. 



DURANIA. 421 

1854. Eadiolites Mortoni, J. Morris. Cat. Brit. Toss., ed. 2, p. 160. 
? — — sp., Morris. Ibid., j). 160. 

1000. BiBADioLiTES MoRTONi, H. Douvillr. Bull. Soc. gcol. de Frauce, ser. 3, 

vol. xxviii, p. 230. 

1904. — — BouviUe. Ibid., ser. 4, vol. iv, p. 174. 

1909. Sauvagesia Mortoni, A. Toucas. Classific. et ]<ivoIut. des Radiolitides 

(Mi'iu. Soc. gcol. de France, Palcont., 
vol. xvii), p. 92, fig. 59. 

1911. IvADioLiTES Mortoni, F. Francke. Zeitsclir. d. deutsch. geol. Gesellsch., 

vol.lxiii, Mouatsber., p. 357. 

Non 1865. — Mortoni, iS'. 1'. Woochranl. Quart. Jouru. Gcol. Soc, vol. xi, 

p. 59, pi. v, figs. 1, 2. 

— 1866. — — K. A. Zittel. Bivalv. d. Gosaugeb. (Deukschr. d. U. 

Akad. Wissenscli. Wien, Math.-uat. 
Cl., vol. XXV, pt. ii), p. 72, pi. xxv, 
figs. 1—3. 

— 1903. — — V. Hilber. Jalirb. d. k. gool. Reichsaust., vol. lii, 

(1902), p. 282. 

Description. — Lower valve at first conical, afterwards becoming elongate and 
cylindro-conical, nearly straiglit or slightly arched. Longitudinal ribs strong, 
angular, sometimes in groups of two or three, crossed by growth-lines. Bands 
concave, with fine ribs ; the interband convex, usually with strong ribs. Radiating 
grooves bifurcate once, twice or more in jjassing from the inner to the outer 
margin. The cellular structure varies in coarseness in different specimens, 
and sometimes becomes rather finer towards the outer margin. Upper valve not 
known. 

AMnities. — One of the specimens figured l)y Sowerby (Dixon, fig. o) is distin- 
guislied from the others by its concave interband with fine ribs and by the narrower 
siphonnl bands ; it probably belongs to another species. 

Bemarks. — Fragments which probably belong to this species are moderately 
common in the Lower Chalk, and in the Cambridge Greensand,' but good specimens 
are rare. Some examples are of considerable size, the largest being a specimen 
from the Cambridge Gi-reeusand, in which the lower valve has a depth of 21 inches. 

Ti/pc.-i. — Mantell's specimens cannot be traced. The examples figured by 
Sowerby (in Dixon, figs. 1 — -h), from the zone of Hohister suhijlobosuti, near Lewes 
(probably Glynde), and the specimen figured by Hudson from Lewes, are in the 
British Museum. 

DlstnbHtion.—Ca.mhrk\ge Greensand (base of Chalk Marl). Probably Chalk 

' Another species of Durania is represented in the Cambridge Greensand by a form with broad, 
slightly concave bauds with fine ribs, and a narrow, strongly concave interband with coarse ribs. The 
bands and iutorband rosoiulilo those of some species of Sauvagesia (Toucas, 1909, pi. xvii, figs. 1,3, 6). 

55 



422 CRETACEOUS LAMELLIBRANCHIA. 

Marl (zone of Schlaenhachiti variaufi) of Ventnor and Folkestone. Zone of Holaster 
suhijlohosns of Burliam and Lewes. Zone of Bht/nchonella Guvieri of Dover. 
Zone of TcrehnitHlina /n^i of "Wouldham. Zone of Holaster 2)hinns of Morgan's 
Hill, Wiltshire. 

Di;i;.vxi.v sp. cf. austixknsi.s {liiimcr), 1852. 

1855. Radiolites Mortoni. S. P. Woodward. Quart. Jouru. Geol. Soc, vol. .\i, 

p. 5i), pi. V, fif^s. 1, 2. 
1904. Biit.\uioLtTES A0STINENSIS, H. DiiiivUlr. Mission Scieut. Perse. Ill, 

fitudes geol. iv, Paleont., 
p. 257. 
1909. S.\uvAGEsiA AUSTiNENSis, A Tdiicmi. Classitic. ct fivolut. des Radiolitidi's 

(Mem. Soc. f,'eol. do Fraiu-e , I'al- 
eout., vol. xvii), p. 96, fig. 6-1. 
rjl2. DuRANiA AusTiNENSi.s, C. F. Parana. Mem. R. Accad. Scienze di Torino, 

ser. 2, vol. Ixii, p. 287, pi. ii, fig. 4. 

Remarhs. — In the specimen from the Upper Chalk figured by Woodward the 
siphonal bands are much broader than in Durania Mortoni, and the ribs on the 
convex interband are finer and more widely separated. The parts recognised by 
Toucas as siphonal bauds were regarded by Woodward as the surfaces to which 
other individuals had been attached. 

This species has been identified with Romer's Hi pjni rites aiistinensis from Texas' 
by the authors quoted above, but, as Prof. Douvillc now points out, this identifi- 
cation must be regarded as uncertain since the essential characters of Romer's 
species are not yet known." The finer structure of the outer layers of the shell 
cannot be taken as a distinguishing feature of Romer's species. 

2)/pe. — Woodward's specimens from Roshcrville are in the British Museum. 

Distribtition. — Zone of Micraster cor-ninjiiiinnn of Rosherville, near Gravesend. 



1 Romer, 'Kreidebild. v. Texas' (1852), p. 77, pi. vi, fig. 1. 

- A few specimens show iudicatious of the ligameutal ridge and appear tt) belong (o the genus 
Satwagesia, e. g. British Museum No. 33957 from the zone of Holader snhylobosus of Sussex, and No. 
L. 4842 from the Turonian of Dover. 



ADDITIONS. 423 



ADDITIONS AND CORRECTIONS. 



AliCA, sp. [Vol. I, p .35] 

Internal casts of a species of Am/ liave l)ocii foiiiul in tlie zoiu' of BcJnnnUcUa 
mucronata of Norwich. Two exani2)lcs are preserve 1 in tlie Norwich Museum (Nos. 
2121, 2122). 



DiCRANODONT.V. [Vol. I, p. -53.] 

Species of Dicranodonttt have now been recognised by Borissjak' in the Jurassic 
deposits of Russia. In connection with this genus or sul)gcuus the papers of 
Solger - and Schmidt ^ should be consulted. 



Crenefxa oRBicuL.VRis {Soicerhi/), 18:56. Plate LXI, figs. 14—17. 

[Ouiitted from Vol. T, p. 105.] 

1836. LcrciNA ? obbiculaeis, J. de C. Soweihy. Trans. Geol. See, ser. 2, vol. iv, 

pp.241, 341, pi. xTi, fig. 13. 
1850. LuciNA OEBicui-AKi.--, A. (V Orhi(j>tij. Prodr. de Pal., vol. ii, p. 162 (jtartim). 
1854. — —J. Morris. Cat. Brit. Foss., ed. 2, p. 208. 

1866. — — F. J. ricfd and G. dimplcJie. Foss. Terr. CrJt. Ste. 

Croix (Matrr. Pal. Suisse, 
ser. 5), p. 201. 
1871. LuciNA? ORBICULARIS, J''. (S/o/(«/m. Palocoiit. ludica, Cret. Fauiia S. liidio, 

veil, iii, p. 252. 

Description. — Shell tliin, small, oval, higher than long, slightly inequilateral, 
regularly convex, Avith rounded margins. Umbones pointed, with a small anterior 
curvature. Lunule and escutcheon not defined. Ornamentation consists of numerous, 
equal, regular, radial ribs which curve outwards from the median line of the valve 
and are separated by narrow furrows. A few growtli-rings occur at intervals. 

' " Pelecypodeu Jura-ablager. EuropoDiscb. Russlaud. II Arcida-," ' Mem. Com. gi'ol.,' n.s., xix 
(1905), pp. 29—32, 58-60, pi. iv, figs. 5—13. 

* "Ueber Pseudociicnll.-ra, cinen iieuen Taxodontcntypus," 'Zeitscbr. d. deutsdi. geol. Gesellscli.,' 
vol. Iv (1903), Monatsber., p. 76. 

^ Il)id., vol. Ivi (1904), Monafslvr.. p. 120. 



424 CRETACEOUS LAMELLIBRANCHIA. 

Measurements : 

(1) (2) (3) (4) 

Lengtli . 7 . 7 . G"l . G inni. 
Height . 8 . 7-6 . 7 . 675 „ 

(1 — I) Blactaown. 

Affinifu's. — This species has been placed in the genus Lncitxi l)y previous 
writers, but Stoliczka suggests that it belongs to Limopsis. Although numerous 
specimens have been seen, none of tlieni shows the character of the liiuge and the 
adductor impressions satisfactorily, l)ut I think that the species should l)c referred 
to the genus Creriella. G. iiijhifa (Midler)' from the Senonian of Aachen is a 
much more inflated form. 

Tvpf . — From Blackdown ; in the Bristol Museum. 

Dlsfrlbitlion. — Upper Greensand (zone of Schld'uharJiia roslratu) of Bhickdown, 
Haldon, Sidmouth. 

Septifer LiNEATi'S {Sowevhi/). [Vol. I, pp. 107, 225.J 

A specimen from the Utnfarriinis band of Devizes Road, Salisbury, has been 
found by Dr. Blackmore. The type of Madiohi (junilratn, Sowerby (in Dixon) 
from Sussex is in the British Museum. 

Vol. T, ]). 117, footnote. The type of Dianchora ? (jntfafn, Sharpe (1853, pi. vi, 
fig. 4), is in the Museum of Practical Geology (Geological Society Collection). 

DiMYODON Boinii, Sfollri/, 1892. 

Grcinwall" states tliat this, or a closely allied form, occurs in the U])por Clialk 
of Gravesend and Grays. 

Vol. 1, [). 1 52, footnote. For " Midler " read " Nilsson." For Ravn " p. '.»," n^ml 
"p. 01." 



Pecten (Ciir,.\MV8) r.iMTT.vNNicus, Woods. Plate LXI, fig. 18. 

[Yd. I, p. 1(!7, pi. xxi. figs. 1, 2.] 

When this species was described only the left valve was known. A speeiuR'n 
from Bromley with the two valves united has since been found. The right valve 

' Holzapfel, ' PalEeontograpliiea,' vol. xxxv (1889), p. 220, pi. xxr, figs. 17—19. 
5 'Geol. Mag.' 190(5, p. 203; Stolley, 'Die Kreide Sdileswig-Holsteins ' (1892), p. 243, pi. vii, 
fig. 8; GiOuwall, 'Meadel. fra Dausk. geol. Foreu.,' No. G (1900), p 78, pi. ii, fig. 8. 



ADDITIONS. 425 

is nearly flat, and tlie broad radial ribs arc much less distinct than on the left 
valve; numerous fine concentric ribs are present, and are widely spaced on the 
early part of the valve, but become closer together on the later part. 

Pecten (CnLAMYs) rKRTOSUS, Defrrnicr. 

Vol. J, p. 170, line 17, delete "Clarendon antl Aldei'bni'y (Halisbniv)." 

Pecten (^quiiecten) cAsnwKiKNSis, irOrhigiii/. [Vol. I, p. 192.] 

A specimen of this species has been found by Dr. Rowe in the zone of 
Micraster cor-tesludiiuifiiiiii of Dover. 

LiM.\ (LiMEA?) sp. Plate LXI, fig. 19. 

[Omitted from Vol. II, p. .52.] 

A few examples of a species which resembles Limea (jraiinlatissiimt, Wollemann,' 
have been found in the Speeton Clay (zone of Bdemuites httcnilis) of Speeton. 
Only a young individual is figured by Wollemann, so that exact comparison 
cannot l)e made at present. 

Suh-r/enus — PsEunorTEUA, Meel\ 

AYhen descriljing the species of rseiuloptera (pp. G-j-OD) I regarded it as a 
sub-genus of Pterin. Ligament-pits have not been seen in any English specimens, 
but their presence was noticed l)y Gueranger- and by Peron^ and indicates that 
Pseudoptera cannot be associated witli Pfcriu, but shoidd prol)ab]y l)e regarded as 
a sub-genus of GcrviUia. 



Gei!Vii.m.\ Forbesiaxa, (rO)7%Hy. 

[Vol. II, p. 85, pi. xi, figs. 26, 27 ; pi. xii. figs. 1-5.] 

This species belongs to the sub-genus Ensigervilleia of Dietrich.' 

1 'Bivalv. 11. Gastrop. J. deutscli. ii. liolluucliseli. Noocoms ' (1000), p. 37, pi. ii, figs. 4, 5. 
-' 'AUnim Paloont. aelaSaithe' (1807), pp. 17, 20, pi. xxii, figs. 9, 10; pi. xxv, figs. 10, 11 
"Woods, 'Palaeont. U. Cict. N. Nigeria' (1911), p. 278, footnote 1. 

3 "Descript. Bnuli. elc, Terr. Crct. Timisie" (1890—91), p. 238. 
* 'Ceutralbl. fiir Miu., etc' (1910), p. 235. 



42G CRETACEOUS LAMELLIBRANCHIA. 

AsTAUTK (Eku'Iiyi.a) concikna, Sourvh)/, 183G. Plate XVII, fig. 7 (soc p. 

llG-118). 

Wlion dcscril)in!4- the species of A.^fartr the only specimen of A. covcinva 
known Avas the type, and I regarded it as probably only an individual variation of 
A. Kfriafa. Dr. Kitchin' has since fonnd several specimens in the Sandgate Beds 
of a pit-sinking at Dover which agree with .1. coiiniina, and he considers that 
this should be regarded as a distinct species. Dr. Kitchin also obtained -I. {Krijilii/hi) 
shiiilii, tSowerby, from the same place. 

ClIASSA'J'ELLlTES, SJ). [Omitted from Vol II, p. 130.] 

Internal casts of a short subqnadrate shell, probably belonging to the genus 
Cfdi^xiif'-lUtes, occur in the Chloritic Marl of Maiden Bradley and Devizes. 

Ckassatelijtes ? EQUisuLCATUS {Wno,]s), 1807. Plate LXT, figs. 20, 21 . Plate LXII, 

fig. 1 . 

[Omitted from Vol. II, p. 130.] 

1897. Aectica? equistjlcata, H. Woods. Quart. Jouru. Geol. Soc, vol liii, 

p. 391, pi. x.Kviii, figs. 6 — 8. 

Description. — Shell convex, subqnadrate, oblique, very inequilateral. Undjones 
anterior, pointed, with slight forward curvature. Greatest convexity between 
the umbones and the postero-ventral extremity ; postero-dorsal part compressed. 
Adductor inq)ressions di.stinct, the posterior one deep. Shell i-ither thick, 
ornamented with numerous concentric ribs, separated l)y nai'ivw grooves. 

licmarloi. — The systematic position of this species is uncertain; it appears to 
be closely allied to the form from the Chloritic Marl mentioned above. 

Type.— In the Sedgwick Museum. 

Disfrihntion. — Chalk Rock of Cuckhamsley, Berkshire. 

Anthonya, sp. [Vol. II, p. 130.] 

A portion of a left valve of AntJiouiia closely resembling A. nnitidud has been 
found in the Upper Greensand (zone of I't'dm anper) of Kingskerswell, Devon 
(Museum of Practical Geology, Jermyn Street, No. 997.) 

1 Lamplugli aud Kitchin, ' Mesozoic Eocks in the Coal Explorations in Kent" (iKll), p. 103. 



ADDITIONS. 42^ 



Cyi'KIXA Mevkiu, Nj). iinr. Plate LXII, iigs. 2, o. 

[Omitted from Vol. II, p. 141.] 

Description. — Shell convex, oval, considerably inequilateral ; anterior margin 
rounded, passing gradually into the slightly curved ventral margin; posterior 
margin truncated ; po3ter(j-(lor.sal margin convex. Umbones prominent, curved 
inwards and forwards, with a rounded carina extending to the postero- ventral 
angle, and limiting a flattened postcro-dorsal region. Lunular region depressed. 
Escutcheon long, deep, limited by a sliarp carina. Ornamentation consists of con- 
centric growth-rings. Length, 5G mm. ; height, 42 mm. 

Affinities. — This species shows some resemblance to C. bi-niemis (Leymerie),' 
but is less elono-ate and much less convex. 

Tijpe. — In the Sedgwick Museum, Cambridge (C. J. A. Meyer collection). 

Dixtrilmti'jii. — Lower Greensand (Pt'r;/'(-bed), of Sandown. 



Cypbina? vectiana {Forbes), 1845. Plate LXII, fig. 4. 

[Omitted from Vol. II, y,. U\.] 

1845. Tellina ? VECTIANA, E. Forbes. Quart. Joiiru. Geol. Soc, vol. i, p. 239, 

pi. ii, fig. 2. 
1854. Tellina vectiana, /. 3/orn'.--. Cat. Brit. Foss., ed. 2, p. 227. 
1865. " Tellina " vectiana, F. J. Pictet and G. Camjiiche. Terr. Crct. Ste. Croix 

(Matt'r. Pal. Suisse, ser. 4), p. 141. 
1871. Tellina? vectiana (? Homalina), F. Stoliczka. PalsBont. Indica, Cijet. 

Fauna S. India, vol. iii, p. 128. 

Descri^dion. — Shell triangular, moderately convex, Mitli flattened sides, nearly 
equilateral. Anterior margin rounded ; ventral margin slightly curved ; postero- 
dorsal margin slightly convex, forming a rounded angle witli the ventral margin. 
Umbones prominent, sharp, slightly curved. Lunular region depressed. Escut- 
cheon long, limited by a rounded carina extending from the umbones to the postero- 
ventral extremity. Ornamentation consists of numerous strong concentric ribs, 
separated by narrow grooves. Length, 25 mm. ; height, 1 7 mm. 

Affinities. — This species shows some resemblance to ('. murato, Sowerby, but 
the shell is much more compressed, and possesses distinct concentric ribs. I am 
not able to determine whether a postero-lateral tooth was present or not. 

» ' Mem. Soc. gcol. de France,' vol. v (1842), p. 5, pi. v, 6g. 6. D'Orbiguv, ' Pal. Fran?. Terr. Cn't .' 
vol. iii, pp. 98, 759, pi. celxxi, and ' Piodr. de Pal.,' vol. ii (1850), p. 77. Picli't and Campiclie, ' Terr. 
Cret. Ste. Croix ' (' Mater. Pal. Suisse,' ser. 4, 1865), p. 212, pi. cxiii, figs 1, 2. 



428 CRETACEOUS LAMELLIBRANCHIA. 

licmiirks. — The type cannot bo found, but other specimens named by Forbes 
are in the Museum of Practical Geology (Geological Society Collection, Ko. 2217). 
DistiibiUioii. — Lower Greeusand (Crackers) of Atherfield. 

Unicahihum ? coMi'KKSSUM, fip. HOC. Plate LXII, figs. 5, G. 

[Omitted from Vol. II, p. 163.] 

Description. — Shell convex, with flattened or slightly concave flanks, oval or 
subipiadrate, moderately or slightly inequilateral. Anterior margin rounded; 
posterior margin subtruncate, slightly oblique, curved ; ^•entral margin nearly 
straight and nearl}^ parallel to the dorsal margin. Umbones broad, close 
together. A rounded carina extends from the umbo to the postero-veutral 
extremity, limiting the compressed postero-dorsal region. External ligament l)road. 
Ornamentation consists of a few coarse somewhat irregular concentric ribs, which 
are sometimes rugose, with finer ribs in the interspaces. 

Measurements : 

(1) (2) 

Length 40 . 32 mm. 

Height 2(3 . 22 „ 

Thickness . . . . . . .17 . — „ 

(1, 2j Crackers, Atherdeld. 

Affinities. — The hinge and interior of this species have not been seen, conse- 
qnently its generic position cannot at present be definitely determined, but it is 
provisionally referred to Unicanlium on account of its external resemblance to 
some Jurassic species of that genus. U.? cowpressum is similar to some forms of 
Jl/yrt vngosa, Romer,^ which has been referred to the genus Lucina by de Loriol 
and Cotteau, to Mactwintjn by Agassiz, and to Unicanlium by Zittel. 

Ti/pe. — From Atherfield, in the Sedgwick Museum, Cambridge. 

Distribution.— Lowev Greensand (Crackers), of Atherfield. Atherfield Clay of 
Dover Colliery. 

Unicakdium r Maillhanltm {tVOrhiijuij), 181k Plate LXTL figs. 7—9. 

[Omitted from Vol. II, p. 1651. 

1844. Cakdium Mailleanum, A. d'Orhiijuij. Pal. Fran^'. Terr. Cret., vol. iii, p. 

40, pi. celvi, figs. 7—12. 

' See especially de Loriol ami Cotteau, ' Mou. I'ak'out. Gcol. I'ortlaudieu de I'Y'ouue" (1868), 
p. 135, pi. ix, figs. 10, 11. 



ADDITIONS. 429 

1850. Cardium Maili.eanum, d'Orhignij. Prodr. de Pal., vol. ii, p. 162. 
1866. — — F.J.PicletandG.Campiche. Foss. Terr. Crt't. Ste. 

Croix (Mater. Pal. 
Suisse, ser. 4), p. 
270. 
1871. — — F. StoUczka. i'alicoul. Indica. C'ret. Fauna S. 

India, vol. iii, j). 213 {Lievi- 
• cardluni). 

Description. — Shell iutlated, oval or subqaadrato, longer than high, moderately 
inequilateral. Anterior margin rounded, passing gradually into the slightly convex 
ventral margin. Posterior margin high, subtruncate, forming an angle with the 
straight postero-dorsal margin. Postero-dorsal part of shell compressed. Umbones 
broad, curved forward. Ornamentation consists of concentric growth-lines and 
fine radial ribs. 



Measurements : 












(1) 


(2) 


(3) 


(4) 


Length 


31 


30 


29 


24 mm 


Height 


27-6 . 


27 


26 


21 „ 


Thickness 


22 


23 


20 


. 16 „ 



Base of Chalk of (1) Beaminster, (2) Maiden Newton, (3) Cerne, (4) TitluTleigli. 

Remarks. — This species was referred to Cardium by d'Orbigny, but the shell 
differs in form from that other Cretaceous species of that genus, and resembles 
more nearly Unicardium. The hinge is not known satisfactorily, but internal casts 
show indications of two cardinal teeth. 

The ornamentation is often imperfectly preserved. 1 am indebted to ]\I. de 
Grossouvre for the opportunity of examining specimens from the Cenomanian of 
Rouen. 

Type. — From the Cenomanian of Rouen. 

Distribution. — Base of the Chalk (zone of Schlcenbachia varians) of Beaminster, 
Cerne, Maiden Newton, Titherleigh and Chard. 

Tkm.tn.v ? PHASKOLiNA {riiHIIps), 1829. Plate LXII, fig. 10. 

[Omitted from Vol. II, p. 177.] 

1829. Mta phaseolina, .T. P/a7/(>. Geol. Yorks., p. 121 (p. 254, ed. 3), pi. ii, 

tig. 13. 
1850. Lavignon phaseolina, A. d'Orbigny. Prodr. de Pal., vol. ii, p. 117. 
1854. Mta i-haseoi.ina, J. iVocci'i!. Cat. Brit. Foss., ed. 2, p. 212. 
1870. Lavkjnon phaseolina, F. Stoliczkn. Pala;out. ludica, Cret. Fauna S. 

India, p. 111. 

56 



430 CRETACEOUS LAMELLIBRANCHIA. 

Description. — Shell small, bean-shaped, convex, considerably inequilateral ; 
posterior part higher than the anterior part. Anterior and posterior uiai-gins 
rounded. Postero-dorsal margin .slightly convex. Ventral margin with a slight 
sinuosity. A rounded carina extends from the umbo towards the postero-ventral 
extremity, and limits a compressed postero-dorsal area. Umbones broad, close 
together. 

Measurements : 

Length . . . 8"o mm. Height . . . 4'5 nnn. 

Affinities. — This .species is more elongate and more convex than T./ snbjiliaseu- 
lina (see below). No specimens having the shell preserved have been found. 

Type. — A specimen which is believed to be the type is in the York Museum. 

Distribution.— y^Yieetow Clay (zones of Belemnites jaculmn and B. brunsvicensis) 
of Speeton. 

Teluna ? SUBPHASEOLINA {(VOrbi(j)ti/), 1850. Plate LXII, figs. 11, 12. 

[Omitted from Vol. II, p. 177.] 

1846. Lavignon phaseolina, A. d'Orbiijny. Pal. Franc. Terr. Crt't., vol. iii, p. 

407, pi. ccclxxvii, figs. 8 — 10. 
1850. — SUBPHASEOLINA, iVOrhignij. Prodr. de Pal., vol, ii, p. 136. 

1865. Tellina PHASEOLINA, F. J. I'ictet and G. Campiche. Terr. Crt't. Sle. 

Croix. (Mati'r. Pal. Suisse, ser. 
4), p. 137, pi. cviii, fij,'. 10. 
1870. Lavignon subphaseolina, F. StoUczJca. Pala?ont. Indica, C'ret. Fauna 

S. India, vol. iii, p. 111. 
— Tellina phaseolina, Stoliczka. Ibid., p. 123 (? Peronxa). 

Description. — Shell oval or subquadrate, compressed, considerably inequilateral, 
posterior jiart higher than the anterior part. Postero-dorsal margin nearly straight ; 
posterior margin curved ; ventral margin with a shallow sinus due to a depression 
on the sides of the sliell ; anterior margin rounded. Umbones small, close together ; 
between the umbones and the postero-ventral extremity is the greatest convexity 
of the shell. 

Measurements : 

(1) 
Length 14 . 

Height 10 . 

Thickness ..... — 

(1—3) Gault, Folkestone. 
Affinities. — The hinge is not shown in any of the English specimens. Pictet 
and Campiche saw casts of the teeth, and they refer the species without doubt to 



(2) 


(3) 


14 


12 mm 


9-5 . 


8-5 „ 


5 


4- „ 



ADDITIONS. 431 

the genus Tellina. Externally, as was pointed out lij^ Stoliczka, it resembles 

Type. — From the Gault of Gcrodot (Aiilie). 
Distribution. — Gault of Folkestone. 



Cvi'KiMEKiA (Cyclorisma) suii.MEKSA (Sou'erhi/), 183G. Plate LXII, fi^'-. 13. 

[For references see Vol. II, p. 192, foot-note.] 

Description. — Shell oval, inequilatei'al, convex, with the postero-dorsal part 
flattened and limited by a rounded carina passing from the umbo to the postero- 
ventral angle. Antero-dorsal margin nearly straight. Anterior margin rounded, 
passing gradually into the moderately convex ventral margin. Postei'ior margin 
truncated. Postero-dorsal mai-gin slightly curved. Umbones of moderate size, 
with a slight forward curvature. Lunule limited by a faint groove. Escutcheon 
elongate, bordered by a carina. Ornamentation consists of small concentric ribs. 

Affinities. — The left valve, which is described above, was found by Mr. Jukes- 
Browne in the Exeter Museum, and appears to be referable to Sowerby's Vemis 
suhmersa, the only apparent diiTerence being in the greater lengtli of the shell. 

The hinge agrees closely with that of C. {Cyclorisma) parva (Sowerby) (p. 185). 
Externally the shell is similar to C. {Cyclorisma) rotomagensis (d'Orbigny), but is 
less convex, more elongated, more inequilateral, with the forward curvature of 
the umbones more marked and the posterior margin more distinctly truncated. 

Distribution. — Upper Greensand (zone of Schlcenbachia rostrata) of Blackdown. 

6r('»».s— Tapes, Megerle von Miihlf eld, 1811. 

[Omiltfd from Vol. II, p. 194.] 

8ub-genus — Icaxoti.\, F. Stolia:l;a, 1870. 
(Palseont. Indica, Cret. Faunii S. India, vol. iii, i>. 145.) 
Tapes (Icanotia) sp. Plate LXII, fig. U. 

Description. — Shell elongate-oval, very incfiuilateral, compressed, anterior and 
posterior ends rounded. Ventral margin convex ; postero-dorsal margin nearly 
straight. Umbones inconspicuous. Ornamentation consists of numerous, close, 
radial ribs which are indistinct on the anterior part of the valve, and become 
stronger and more widely separated on the posterior part, where a small rib may 
occur between two larger ones. Length (approximate) 55 mm., height 20 mm. 



432 CRETACEOUS LAMELLTBRANCHIA. 

Affiititu's. — Only tAvo right valves of this species have been seen. They 
resemble closely Capan ('/'^//(/hs, d'Orbigny,' l)nt the ribs on the posterior part of the 
shell are more numerous and less coarse. 

Distrihution. — Upper Greensand (zone of SchJceithachui roHtrafa) of Blackdown 
and Ilaldon. 



Leptosolkn r KKiTANcrr.Auis (IFuoJ.v), 1897. Plate LX 11, tigs. 1-j— 17. 

[Omitted fmm Vol. TI, p. 221.] 

1897. Trapezium ukctangulake, H. Womh. Qiuirt. Journ. Gt'ol. Soc, vol. liii, 

p. 392, pi. -xxviii, figs. 11. 12. 

Desrrijifiun. — Shell niure or less oblong, very inequilatei'al, moderately convex, 
with flattened or slightly concave sides. Anterior part not so high as the posterior 
part. Postero-dorsal margin nearly straight and nearly parallel to the ventral 
margin ; anterior margin rounded ; posterior margin truncated, slightly convex or 
nearly straight, and almost at right angles to the postero-dorsal margin. Umbones 
inconspicuous, with a carina extending in a curve to the postero-ventral angle, and 
limiting a triangular postero-dorsal area. A strong internal ridge extends from 
the und)o towards the opposite ventral margin. Length 19 mm., height 11 mm. 

Affinities. — A similar species has been referred doubtfully by "Weller- to 
LepioHolen. J/odiohi tetniijona, Reuss,^also shows some resemblance to the English 
species. The hinge is not shown in any of the specimens, and the generic position 
must be regarded as uncertain. 

Type. — In the Sedgwick Museum, Cambridge. 

Vi.^fribution. — Chalk Rock of Cuckhamsley, Berkshire. 

Vol. II, page 2-30, line 5 from the bottom, for " variiciis^' read " rastvafa." 
Tiii!Aci.\? (JiiAcius {Soirerhi/), 1S:?(;. Plate LXII, figs. 18, 19. 

[Omitted from Vol IT, p. 244.] 

1830. PsAMMOBiA? GRACILIS, J. (le C. Soicerhij. Tr.aus. Geol. Soc, ser. 2, vol. iv, 

pp. 2-12, 3-11, pi. xvi, tig. 12. 
1850. Tellina gracilis, A. (VOrhujmj. Prodr. de Pal., vol. ii, p. 159. 
1854. Psammobia gracilis, J . Morris. Cat. Brit. Fo.ss., ed. 2, p. 222. 

' 'Pal. Fianc. Terr. Cret.,' vol. iii (1845), p. 423, pi. ccclxxxi, figs. 1, 2. 

- • Cret. Palffiont. Now Jersey ' (1907), p. 626, pi. Ixx, fig. 29. 

^ 'Die Vcrstciii. der bOhm. Kreideformat.,' pt. 2 (1846), p. 15, pi. xxxiii, fig. 6. 



ADDITIONS. 433 

180.5. Tei.i.ina ciRACii.is, F. J. Pictet <ini <l. Campichc Foss. Terr. Cn't. Ste. 

Croix (Mati'r Pal. Suisse, 
ser. 4), p. 138. 
?1868. — — A. Biinrt nnil F. L. Cnnicl. Meule de Bracquegnies 

(Mt'm. cour. et Mem. des Sav. 
ctrangers, vol. sxxiv), p. 80, 
pi. vii, fig. 19, 20. 
1870. — — F. StoUczka. Paloeont. Indica, Cret. Fauna S. India, 

vol. iii, p. 123. 

Description. — Shell (.'loiigate-oval, moderately coiive.x, slightly iiiecjuivalvc and 
inequilateral. Anterior margin rounded. Ventral margin slightly or moderately 
convex, and forming an acute angle with obliquely truncated posterior margin. 
Umbones incurved. A sharp carina extends in a curve from the umbo to the 
postero-ventral angle, and cuts off a flat or slightly concave postero-dorsal area. 
Ornamentation consists of concentric ribs, which are less numerous but stronger on 
the anterior part of the shell and the postero-dorsal area than elsewhere. 

Measurements : 

(1) (2) 

Length .... 14 . 8 nnn. 

Height .... G . 4 „ 

(1, 2) Blackdowu. 
Affinities. — This species resembles Thracia clrgiinH (d'Orbigny)' but possesses 
stronger concentric ribs. Its generic position caniidt l)e determined definitely 
since only a few specimens have been seen, none of which shows the hinge or 
interior. 

Type. — The type from Blackdown cannot be found. 

Distribution. — Upper Greensand (zone of Schlcjcnljachia rostrata) of iilackdoNVti. 



iNOrEliAMUS TUBERCUr-ATUS, Woods. [See Vol. II, p. 302.] 

An example of this species has been found in the zone of Artinocamnx 
quadratus of East Harnham, Salisbury, by Dr. Blackmore. 



Inoceeamus intermedius, Soicerhij. 

[Loudon's ' Mag. Nat. Hist..' vol. ii(1829), p. 296, fig. 83 ] 

The figure given by Sowcrby of a specimen from Norfolk ai)pears to have 
been overlooked by previous writers; it probably represents a large form of 
/. Lamarcld var. apicalis. 

' • Pill. Franc. Terr. Crct.,' vol. iii (1845),'p. 38(5, pi. ccclxxiii, figs. 3—5. 



4:3 



CRETACKOUS T.A:\IKTJJBRAXrHTA. 



I.— DISTRIBUTION OF THE LOWER CRETACEOUS SPECIES IN ENGLAND. 

The genera are arranged in tlie order of the classification followed in tliis work. The species of 
each genus or subgenus are iu alphabetical order. The stratigraphical divisious are tlio.se a.lopted in 
the ' Memoirs of the Geological Survey.' 



Genus and Species. 



Volume 
and 
Page. 



NUCOLANA 

scapha ((rOci.) ' 1,3 

Seeleyi (Crf/rrf.j I. •'> 



spathulata (Forh.) . 
speetonensis, Woods 
subrecurva (PA ///.) . . 



NtrcuLA 

Lanipluglii, Woods 

Meyeri, Gard 

planata, Desk 

sp. [Cornueliana, Gard. non d'Orb.] 
sp. [simplex, Gard. non Desh.] 

Anomia 

convcxa, Sojy 

laevigata, Sow 

pseudoradiata, d'Orh 



Arca 

Carteroni, fZ'Orfc 

Dupiniana, d'Orh 

Sancta-'-Crueis, Fid. & Cam}). 

Barbatia 

aptiensis [Pict. S: Camp.) 

marullensis ((7'0r/(.) 

(Scaphula ?) Austeni (Forh.) 

Gramhatodon 

securis (Leijm.) 



CUCULL.SA 

Cornueliana (d'Orh.) 

Fittoi.i {Pid. A- Camp.).. 
Forbesi (Pid. & Camp.) 
vagans, Keep. .. 



1,1 

1,3 
1,2 



I, 14 
1,15 
1,12 
I, 13 
I, 14 



1, 29 
I, 29 

I, 27 



I, 33 
1,32 
T, 34 



I, 35 
I, 38 
1,37 



1,44 



I, 50 
I, 52 
1,49 
1,52 



Yorkshire, Lincolnshire, 

Norfolk. 



. o 
to g 

CO 



s ■ 

s 

n 



«►-> 



s 






,2^ 



X 

X 



Cambridfje- 

shire to 
Wiltshire. 



pa 



c3pq 
s - 



o ca 



X 
X 



a 

"a 

5 = 



O ° '~' 






i. -t 



o d 



riio Weald and 
Isle of Wi-jht. 



B 

1) iS 



— B r 






X 

X X 



X 
X X 

X X 



B o 



^2 



X X 
X X 

X I ? 



LOWER CRETACEOUS. 



43^ 



Oenus and SjH'cies. 



Volume 

and 
Pa<'e. 



CuCULLjExV 

(Dicranodoiita) tloimiugtoiieusis, 

Keep 

— obliijua I^Keep.) 

Pectunculus 
niarulleusis, Leym 



Trigonia 

carinata, Acj 

cauilata, Ag 

Etheriilgei, i^r 

exaltata, Lijc 

ingeus, Ltjc 

nodosa, Sow 

oruatii, d'Orb 

Kobinalclina ?, d'Orh. 

scai)ha, Ag 

tealhyensis, Lye. 
upwarensis, Lye. 
vectiaua, Lye 



Mytiltjs 

sp., cf. toruaceiisis, (VArch. 



MODIOLA 

iBqualis, Sow 

ligerieiisis (rf'Oi'fc.) 

rugosa, i?rin? ■ ■ 

subsimplex ((Z'0r6.) 

unilulata ( Foc6.) 

(Brachydontes) vectieu&is, Woods 

Cbenella 

bella {Sow.) 



Septifer 

liiieatus (Soic.) 

Dkeissensia 

laiiceolata {Sow.) 

Spondylus 

Eoemeri, Desk. . 
striatus {Sow.) 



Plicatdla 
sequicostata, Keep. 



Yorkshire, Lincolnshire, 
Norfolk. 



. o 



a « 



SI 



I, 54 
1,55 



1,66 



1,90 
1,81 
1,81 
I, 74 
1, 75 
1,78 
1,85 
I, 74 
I, 73 
1,79 
1,86 
1,84 



1,01 



1,92 
1,96 
1,97 
1,97 
I, 100 
I, 102 



I, 104 
I, 10(! 
I, 110 



I, 116 
I, 119 



I, 136 



9 "= 
o e 

ISl i-s 



2 s > " 

C 5 ? ii 
o 

ESI. 



... I 



Cainbridf,'!'- 
%Hhirc to 
Wiltshire. 



P4^ 

CO . 

o o 
OP 



o « 
I-:] a 



a 
"3 
o 



1-^ ^ 



VUi^ Woald and 


Isle of Wight. 










a 




X 


fr.2 

"5 « 


35 


'£ 'in 


n a 






o 'p 


<- 


Wffl 


^■^ 
i.1 




X 




X 


X 
X 




X 






X 


X 


X 


X 


X 




X 


X 


• 


X 


X 


X 


X 


X 




X 


X 




X 






X 


X 




X 


X 
X 




X 


X 




X 







436 



CRETACEOUS LAMELLIBRANCHIA. 



I'luis :iiul Species. 



Volume 

and 

Paffe. 



Plicatula 

Carteroniiina, (/"Ort 1,13.') 

jilaciiiuM, L(n» I,131' 



Pkctbn 

(Syucycloneiua) orhiciilavis, /S'ow. .. 
(Cam|it-()iioctes) ciuctus, Sow 

— CottalJinus, d'Orb. 

— striato-puuctatus, 
Riiiu 

(Chlainys) Roliiualdiuus, d'Orb. ... 
(Neitbea) atavus, Ei'im 

— Moi-risi {Pict. d- Ren.)... 

— qiiiiii|ueL'Ostatus, Sow. ... 

lIlNNITES 

Favriuus, Pict. & Rou.i 



OSTREA 

canaliculata, Soio 

diluviana (L.) 

Leymerii [Bi'sJi.'] Leijm 

vesicularis, Sow 

Walkeri, Keep 

ESOGYRA 

couica (Sow.) 

siuuata (Sow.) 

tubeiY-ulifera, Koch & Bunk 

Lima 

(Plaglostonia) subrigida, R.iin 

— sp. c/. Orhiguvaua, 

Math ; 

— sp. cf. villersensis ?, 

Pict. & Camp. .. 

(Acesta) louga, Brim 

(Mantellum) f arriugdoiieusis, Sharpe 

— parallola (iS'oic.) 

(Liinatula) Diij)luiana, iVOrh 

— Toiubtvkiaiia, d'Orb. ... 
(Limea ?) ssp 

Pteria 

(O.xytoma) Coruneliana (d'Orb.) .. 

— pectiuata (Sow.) 

AUCELLA 

Keyserlingiana, Tra titsch 

volgeusis, Lahiia 



I, 145 
I, 152 
I, 15G 

I, 157 
I, 181 
I, 197 
1,201 
I, 202 



I, 220 



II, 375 



Yorkshire, Lincolnshire, 
Norfolk. 



Ji, 


34;i 


II. 


355 


II, 


360 


II, 


3G0 


II, 407 


II, 


395 


II, 


404 


11 


10 


II 


12 


II. 


13 


II, 


25 


II, 


30 


II. 


28 


II. 


47 


II. 


45 


II, 


4-25 


II. 


57 


11. 


59 


II. 


70 


II, 


69 




LOWER CRETACEOUS. 



437 



Gcuus and Species. 



Geevillia 

alaeformis (iSoiw.) 

Forbesiaua, d'Orb 

linguloides, Forb 

sublanceolata ((rO/"6.) 

(Pseudoptera) subdepressa (d'Orb.) 



Perna 

Mulleti, Desk 

Bicordeana, d'Orb. 



Inoceramus 

ueocomieusis, d'Orb. 

Salomoni, fZ'0r6 

SP 



Pinna 

Eobinaldiua, d'Orb. 



ASTAETE 

cautabrigieusis. Woods ... 

claxbieusis. Woods 

elougata, d'Orb. 

senecta, Woods 

sinuata, d'Orb 

subacuta, rf'Ort 

subcostata, d'Orb. 

upwareusis. Woods 

sp 

sp ; 

(Eriphyla) coucliina, Soiv. 

— lajvis (Phill.) 
■ — obovata, Sow. 

— striata, Sow. . 

Opis 

neocoiniensis, d'Orb 



Caedita ? 

feuestrata (Forb.) 

Cardita 

upwarensis, Woods . 

sp 

sp 

Anthonya 

cautiaua. Woods .... 

sp 



Voluiue 

and 
Page. 



II, r;i 

II, 85 
II, 78 
II, "4 
II, 63 



II, 87 
II, !10 



II, 262 
II, 263 
II, 263 



11,96 



II, 107 
II, 108 
II, 102 
II, 106 
II, lot 
II, 103 
II, 109 
II, 10-5 
II, 107 
II, 111 
II, 426 
II, 115 
11, 113 
II, 116, 
426 

II, 118 



II. 121 

II, 122 
II, 123 
II, 123 

II, 130 

II, 131 



Yorkshire, Lincolnshire, 
Norfolk. 



. o 



P, o 



a Z 
o e 

N 1-3 



"» « 

« ; 



.Sk 



Cambridge- 
shire and 
Wiltshire. 



P.-3 

-73 -r; 

OJ o 
u *^ 

t 9 



u so 



t-3 Ut 



The Weald and 
Isle of Wight. 






J3 



■a 

-eg 



X X 
X 



P5 B 



^2 



57 



438 



CRETACEOUS LAMELLIBRANCHIA. 



Genus and Spesics. 



Cypkina 

auglica, Woods 

claxbieiisis, Woods 

Meyeri, Woods 

obtusa, Jrcrj) 

(Veuilicanlia) proteusa. Woods. 

Saussuri {Brojniii.) 

Sedgwicki (WaUc.) 

Sowerbyi, cVOrb 

tealbieusis, Woods 

? vectiana (Forbes) 

sp 



rRAPEZIUM ? 

avcadiformo (Keep.) 
sqiiaiiiosuni {Keep.) 
sp. ('/. striata. Geiii.). 



LUCINA 
sp. . 
sp. . 
sp. . 



CORBICELLA 

claxbiousi.s, Woods 

SriiAiRA 

corru;4ata, Sow. ... 



Unicardium 
claxbieiiSL', Woods .... 
? coinpressuni, Woods. 
vecteuse, Woods 



Thetironia 
miuor {Soiv.) 



Tellina 

Carteroui, d'Orh. 
(Linearia) sp. 



Tellina ? 

phaseolina (VhiU.) ... 

Mactba 

sp 

Ptychomya 

Rol.iiialdina (d'Orb.) 



Volume 

and 

Page. 



Torkshire, Lincolnshire, 
Norfolk. 



II, 
II, 
11, 
II, 
II, 
II, 
II, 
II. 
II, 
II, 
II, 



l:i7 
18.5 
427 
133 
137 
131 
133 
139 
136 
427 
136 



^ S 






II, 148 
II, 148 
II, 149 



II, 152 
II, 152 
II, 153 



II, 157 



II, 15 



II, 
II, 
II, 



162 

428 
163 



II, 167 



II, 
II, 



II, 
II 
II 



171 
175 



429 
177 

179 



Bq 



« 1. 

^3 



o; 



N 1-1 



a c 
o t 



a M 



Oaiubrid^'o- 
shire and 
Wiltshire. 



p9 



'CL, 






X 
X 
X 



..-. [.,.. 



CO * I « 

c a , c : 






Tlie Weald and 
Isle of Wight. 



-a o 
S.S 
73 y 



a <- 

Km 



I 
a a 

CO 

4-1 1) 
0> H-l 

\^^ 

\l.o 





X 




X 


X 


X 




X 


X 


X 


X 


X 


X 


X 


X 


X 




X 


X 


1 X 



LOWER CRETACEOUS. 



439 



Genus ivnd Species. 



Cyprimeria 

(Cjclorisina) parva (Sow.) 

— veetensis (l^o?-6.)... . 

Clementia 

(Flaveutia) Eicordeaua {d'Orh.) 

Peotocardia 

ani^'lica. Woods 

spliffiroidt'a (Forh.) 

sp. ((■/. peregrinorsa, d'Orh.) 

Caedium 

CottalJiuura, d'Orh 

Ibbetsoui, Forh 

sp 

Toucasia 

Lousdalei (Sow.) 

COEBULA 

ans,'ulafa (P/j)7?.) 

striatula, Sow 

Phaetjs 

Warburtoui (Forh.) 

Panopea 

gnr!,'itis (Brovgn.) 

luaiuliliula (Soiv.) 

spilsbieusis, Woods 

sp 

sp 

Martesia 

coustricta (P/i!7/.j 

prisca (Sotv.) 

TURNUS 

Dallasi (Walk.) 

Plectomya 

anglica, Woods 

Anatina 

(Cercouiya) gurgitis, Pict. & 
Camji 



Volume 

and 



II, 184 
II, 183 



JI, 189 



II, 194 
II, 195 
II, 197 



II, 203 
II. 201 
II, 204 



II, 207 



II, 210 
II, 212 



II. 217 



J I, 222 
II, 228 
II, 222 
II, 221 
II, 230 



II, 231 
II, 232 



II, 233 
II, 238 

II, 239 



Yorkshire, Lincolnshire, 
Norfolk. 



ea 

X . 

W a 

. o 

'■" a 

9 a 

° o 

a, N 



S 

s 

"^ 
05 . 

SI 
a <» 

tsi.S 



oi 

a c 



r-^ 



Cambridge- 
shire to 
Wiltshire. 



t3S 



■ Ck 



t^ ^ 



C 
a a 

CS 0) 
CO OJ 

a M 

a> - 
P a 
O -a 

S a 

5 S 



The Weald and 
Isle of Wi<rht. 



-3 



CO 

a 

60 2 

"2 ° 



Wffl 



CO -^ 
O T3 



410 



CRETACEOUS LAMELLTBRANCHTA. 



Genus and Spocics. 



Thracia 

Phillips], EiJm 

EobinaklinaV (d'Orb.) 
rot uiulata (iS'ow.) 

Pholadomya 

Coruueliana ((^Orfc.) 

gigautea (Sov.) 

Martini, Forh 

speetouensis, Woods 

Myopholas 

sp., (•/. semicostatus (Ay.) 

GrONIOMYA 

Avcliiaci {Picl. £■ Ren.) ... 

Pledromya 

Orliiguiaua (Eouill.) 



Vohinic 

and 

i'ase. 



11, 240 
ir, 242 

II, 241 



IT, 246 
II, 24G 
JI, 249 
II, 248 



II, 253 
II, 254 

II, 256 



Yorkshire, Lincolnsliire, 

Norfolk. 



W a 









O. o 

tea 



«0 


. 






















s 


S y 


.s 


^•2 






a? . 


«! ? 


e*-t S 


**-« .^ 




c ^ 




ffl 2 


c C 


c s 


O £ 


o ■: 


^^ 


N Jj 



=«.s o 



iz 



S tJ^ 



Cambridge- 


shire to 


"tt'iltshire. 


p.— 


o 
a 


^a 


•R3 


O 


^.y 


13 "C 


^i- 


S ? 






a c 


a M 


O o 


o - 




c- a 








CS-o 
£ a 






The Weald and 
Isle of Wight. 






09 

a 

0) cS 
QJD s 

11 

02 M 



§1 



a a 
CO ^ 
oi J5 

ffl a I 
o =* 
a ^ 

2M 






X 
X 



X 
X 
X 



UPPER CRETA(1K()US. 



Ul 



II.— DISTRIBUTION OF THE UPPER CRETACEOUS SPECIES IN ENGLAND. 



Genus nnd Species. 



NtJCnLANA 

angulata (Sou).) 

lineata (Soi